NOVA PROS Home Improvement Resource » Safety

How to Winterize a Hot Tub

admin — Mon, 27 Sep 2010 12:00:44 +0000

Winterizing your hot tub

The hot tub is one of the most fun items in anyone’s backyards, and many people like to enjoy their hot tub all year round. There is nothing wrong with jumping into the hot tub when the snow lies deep and thick in the rest of the yard, but some people do prefer to winterize their hot tub. Again there is nothing wrong with winterizing the hot tub, but problems do arise when the winterization is not done correctly, and these problems can be expensive ones.

The first step in winterizing a hot tub is to ensure that all electrics, including the heating system, are turned off. Then it is necessary to start the draining process. Most of the water within a hot tub can be easily removed by opening up the drain, but the use of a pump will aid the removal of water from crevices like foot wells. This process will remove the majority of water, but the removal of the majority of water is not sufficient. The major problem with incorrect winterization of hot tubs is that water is left, expands and damages parts of the tub.

To remove all water from a hot tub, there are several additional steps that need to be taken. The use of a towel, sponge, mop or similar product will help soak up the remnants of water, but it is also necessary to find out where any water is lurking. Some hot tubs will come with air blowers and these will also need to be cleared of water. This will require the power to be reconnected, but allowing the air blowers to run for a few seconds will clear any water remnants.

Filters can then be removed, cleaned or replaced, before stored somewhere safe. Water will also remain behind many of the hot tub’s fittings. Most new hot tubs will have easy to remove fittings, especially around the heater and pump. By simply loosening these fittings, water will start to drain away but any residue should be pumped away or soaked up. Jet pipes will also need to be cleared in a similar way, although blowing the water out is normally a more effective approach.

The hot tub cover should then be put in place. Ideally this will be a hard cover, as it makes it a lot easier to secure and also make watertight, as well as rodent tight. If the winter is anticipated to be extremely harsh, an additional winter hot tub cover should also be purchased and put in position.

Many places that sell pool and hot tub supplies will offer a range of antifreeze products for the hot tub. There are some good products in the marketplace, but there is always the problem of removing all traces of product when the hot tub is to be used again.

After correct winterization, the hot tub should be in a perfect position for the spring.

Many people prefer to hire in professionals to winterize their hot tub, and this is certainly the safest approach, if not the cheapest in the short term. It is always better to err on the side of caution when winterizing a hot tub, but with care and attention it is still something that any homeowner can do.

Correct winterization will ensure that a hot tub has a long life. Ensuring that water can not freeze and cause damage is essential, and this includes removing all water, but also preventing any snow from entering the hot tub after draining.

Article by Tim Harry. To read more articles by this author, go to Helium.

Don’t Let Termites Eat Away the Sale Of Your Home

LillyTeam — Mon, 20 Sep 2010 12:00:15 +0000

Termite Infestation

You’re selling your home and it comes time to get that dreaded termite inspection. It’s the Wood Destroying Organism (WDO) inspection that homeowners fear can eat away at the price of a home or ruin the entire deal–but it doesn’t have to.

There are a few signs that may indicate there might be an infestation. Some states are more likely to have heavy termite activity such as those in a “hot zone” such as California, Texas, Mississippi, Alabama, Louisiana, Georgia, South Carolina, Florida, and Hawaii. While these areas have the highest level of activity, termites can be found nearly anywhere and the varieties of the insects differ depending on the area and climate.

According to TermiteInstitute.com, “When conditions like cracks in the foundation or plumbing leaks are present; the possibility of a hidden wood-destroying infestation exists. Buyers should pay particular attention to these potentially hazardous conditions outlined in the WDO inspection report.”

Many homeowners don’t think about the possibility of having termites until they’re getting ready to sell their home. Unfortunately, a history of termite issues can eat away at the sales price. Being prepared and understanding what to expect from an inspection is not only helpful but could help ensure a better price and smoother home sale.

TermiteInstitute.com has a lot of information that helps clarify the type of termites found in various locations. The site also helps inform and educate people about termite warning signs, treatment, and even the biology and lifecycle of these pests. I found the site’s top questions and answers about termites to be very interesting. Here’s what you should know about termites.

If my neighbor’s home is infested; will mine be attacked next? TermiteInstitute.com says not necessarily. However, the risk is, of course, high. Preventive treatment is recommended.

How are homes treated for termites? The methods vary depending on the severity and the professional company that you choose but here’s a look at some modern treatments.

Termite bait systems can be set up, however, this requires termites to find the bait stations, eat the poisonous feed, and then transfer it to the colony. It can take up to a year to be fully effective.

The site says that liquid termite treatment is known as the new “undetectable” or “non-repellent” technology. “It works well with subterranean termites, which comprise about 90 percent of the infestations in American households.” This method is done by a professional applying the undetectable liquid to the soil and around the home as well as critical points in the structure where termites are likely to invade.

Since termites can’t detect the liquid material, they pass through the treated soil causing termite mortality. “However, before termites die, they can have an opportunity to return to the colony and transfer the material to others in the nest,” according to TermiteInstitute.com

Will my homeowners’ insurance pay for treatment? It’s not likely. Although, in some areas of Louisiana some insurance companies have covered termite treatments for those structures that suffered hurricane damage.

While termites are annoying and can certainly eat away at your sale price, if you don’t take care of the infestation and damage, they’re not harmful to humans. In other words they feed on wood, not people. But they can severely damage a home so it’s best to know right away whether you have an infestation and what your options are to resolve the problem. It could save you money and frustration when it comes time to close the sale on your house.

Written by Phoebe Chongchua as found in Craig Lilly’s Newsletter.

Building Permits

StructuralSupport — Tue, 13 Jul 2010 21:14:48 +0000

For many Americans, the term “building permit” tends to evoke thoughts of Soviet-style bureaucracy. Homeowners often consider building permit regulations to be a police-state type intrusion, even when they actually know next-to-nothing about the process. Contractors all-too-frequently “persuade” owners to have work performed without a permit to avoid the perceived hassle of those dreaded inspectors.

“Fear-of-building-permit” affliction is mostly not justified. A building permit is actually worthwhile protection for the owner. However, to ensure full benefits and avoid potential delays, homeowners should obtain basic knowledge about the permit process before embarking on a building project, whether a new house or a kitchen remodel.

PURPOSE OF BUILDING PERMIT
When crossing a bridge, especially a long, high span over water, we clearly understand the need for safe construction. Those who have been inside buildings during hurricanes or earthquakes also realize (very clearly) the critical importance of proper construction.
During more usual daily events, we tend to forget about safety of building construction. In general, such lack of concern is expected and necessary so we can focus on solving more immediate problems. However, ensuring building safety remains an essential function that should not be neglected.

A building permit is one tool that can be useful in the effort to provide safe buildings.

Constructing a new building or making changes (alterations) to elements of an existing building must be done properly to ensure safety of occupants, both current and future. Though difficult for current owners and occupants of buildings to admit, they will almost certainly not outlive the building unless it has already started to collapse. The building essentially has a “life” of its own and will serve new owners. The permit process, when applied correctly, helps to ensure that building safety is maintained throughout the life of the building.

BUILDING PERMIT PROCESS: GENERAL
In the US, each municipality (city, township, borough) or county generally has a building department that is responsible for managing the building permit process.

Key code officials, such as construction official, are typically local government (municipal, county) employees. For small communities, code officials may be state employees. Building inspectors are often government employees also. However, inspection functions may be subcontracted out to private-sector firms.

The property owner is always responsible for the permit, even if the builder or contractor (as owner’s agent) handles the paperwork.
Basic information must be included on the permit application, including names of owner and contractor, general description of proposed work and estimated cost. Permit fees, typically based on type of construction and estimated cost, are supposed to cover the cost of plan review and inspections by code officials and inspectors.

Regulations set time limits for code officials to review and release the permit application, as long as there are no outstanding design issues (see Plan Review). Many building departments turn permits around in several days. However, the owner or contractor should call the code office if there is some delay without explanation.

The permit (when issued) typically is valid for a specific time limit, such as one or two years. If construction has not started before the limit expires, a new permit may be required. Permits may be amended to include additional construction. Revised design plans may be required for such amendment.

ONLINE INFORMATION
Information about building permit requirements is available online. Many communities provide building permit application forms. The following samples from around the US illustrate some of the better information and capabilities provided:

Baltimore, Maryland
Austin, Texas
Freehold Township, New Jersey
Oakland, California
State of Washington
US Census Bureau

RESPONSIBILITY FOR DESIGN
Building design is a separate function from construction. The general public often does not understand that some person or persons other than the builder are responsible for design.

For any building that serves the public, state laws require that a licensed architect or engineer must design the building. The design professional (architect or engineer) prepares design documents (plans & specifications) to show construction requirements for the completed building. Plans and specifications must satisfy requirements of the applicable building codes. Design documents, submitted along with the building permit application, become the key documents governing construction.

For single-family houses, plans may be prepared by the owner or builder, depending on state regulations. Quality of such plans is often severely deficient.

PLAN REVIEW
During the permit process, plans and specifications are reviewed by various code officials responsible for specific aspects or “systems” such as framing and foundations, mechanical, electrical and plumbing. However, intent of “plan review” is only to ensure that; (1) Plans have been prepared by qualified person or persons, and (2) In general, plans and specifications conform to basic requirements of the building code.

The public has the very common misconception that code officials “approve” design plans. In fact, code officials are almost universally not licensed architects or engineers and are therefore not qualified to completely check or approve design plans.

When the building code includes prescriptive provisions, code officials may use such provisions to review plan details. However, code officials more typically seek to ensure that overall quality of plans appears to be adequate. In practice, code officials tend to focus on the most obvious “life safety” issues, such as fire protection.

Quality of plan review varies greatly. Code officials may be overloaded such that they have time to perform only cursory review.
Whether code officials perform detailed plan review or not, the responsible design professionals remain completely responsible for quality of plans and specifications. Inadequate design plans can cause major problems during construction.

BUILDING INSPECTION
Building inspectors use plans and specifications to inspect construction work. However, similar to plan review, quality of inspection varies greatly.

The public has the common misconception that municipal building inspectors “certify” every element of construction. In fact, building inspectors only perform limited inspections to determine that, in general, construction conforms with requirements of design plans.
Whether building inspectors perform detailed inspections or not, the builder / contractor remains completely responsible for quality of construction.

When design plans do not include necessary information, major problems can be expected. The inspector should insist that the builder obtain revised plans from the responsible design professional. However, in practice, inspectors generally “overlook” such deficient design and allow the builder to make design decisions to “fill in” the missing information. Major legal claims have resulted from this all-too-often practice.

ENDGAME: CERTIFICATE OF OCCUPANCY
After final inspections are performed, the responsible code official issues a “certificate of occupancy” which is required before anyone can occupy the building.

Similar to other misconceptions about the role of code officials and inspectors, the public has the general misconception that issuance of a certification of occupancy means that code officials “approve” of the entire design and construction. Builders often use this misconception to divert attention from themselves when building defects are discovered.

Essentially, the certification of occupancy means only that code officials have completed their responsibilities in accordance with state regulations.

AFTER-THE-FACT PERMIT
Many owners and contractors seek to avoid the permit process entirely. Saving cost of the permit fee is given as one reason. However, avoiding the need for design plans and the perceived “hassle” of inspections are usually much more important as reasons for skirting the building permit.

Initial “savings” all-too-often end up costing owners much more in repair costs to fix defective construction. Lack of a building permit is often revealed during a real estate transaction. Owners can then be faced with significant cost to show what was built. In some cases, code officials may require partial or complete removal of interior finish materials to allow for inspection. Threat of fines (some quite high) may be used by code officials if the owner attempts to resist an order for an after-the-fact permit application.
Sometimes, current owners were not aware that previous owners had performed construction without a permit. Current owners may then find themselves “on-the-hook” for obtaining an after-the-fact permit when they try to sell the house.

For more articles by this author, go to Helium.

John F Mann, PE
Structural Support
1212 Main Street
Belmar NJ 07719
732-556-6080
www.structural101.com

How to Remove Ice from Driveways

admin — Mon, 01 Feb 2010 12:00:54 +0000

As the snow falls, driveways soon become covered and unless action is taken, it will not be long before a layer of ice has built up. Removing ice from driveways can be done in a number of ways, but there is a cost involved, either in effort, money, time or a cost to the environment.

Most people prefer to make use of salt to de-ice their driveway. Salt, or sodium chloride as it is also known, has been used for many years, and is often just sprinkled over the driveway to remove ice. There is though a cost involved, despite it being one of the cheapest options. Salt will work fairly fast in removing ice, but can cause damage to the driveway, as well as to the metal of any car that drives over it. Additionally salt will harm plants as it prevents them absorbing nutrients and moisture. Salt will only work when the temperature is in excess of 18 degrees Fahrenheit.

There are other chemicals available which will do a similar job to salt. Of these others the most common are Potassium Chloride, though this will also harm plants and is slower working that salt. Additionally Potassium Chloride only works when the temperature is above 25 degrees Fahrenheit.

Faster working is Calcium Chloride and Magnesium Chloride. Calcium Chloride will harm concrete and plants alike, whilst Magnesium Chloride will also harm plant life. All of the chemicals do remove ice from driveways, but there is a cost often to the driveway and the environment, and ice can reform fairly quickly if temperatures continue to rise and fall.

The old methods are still the best and shoveling snow and ice is the best for the environment and the driveway surface. If thick ice has been allowed to build u,p then a shovel is not the best tool to break it up. Many stores now sell ice chippers, tools which will break up ice, allowing them to be shoveled away. Care needs to be taken when using shovels and ice chippers, as too much force could see the driveway damaged.

Having cleared away the ice, then it is best to add some sand to the driveway. Sand itself will not do anything to the ice but will aide traction for both cars and pedestrians.

Removing ice from driveways is a chore but it is a necessity come wintertime. There are a number of options available to remove the build-up of ice but there is a price with each.

Written by Tim Harry. Find more articles by this author at Helium.

Is Your Home Wired Properly?

LillyTeam — Tue, 22 Dec 2009 15:27:29 +0000

We all know that as things age, they often need replacing but sometimes homeowners neglect to take care of their home’s electrical wiring and that can set them up for potential danger. Electrical consumption since the middle of the last century has increased in most homes on average about 400 percent.

If you’re tripping your main safety circuit box that could be a sign that you’re overloading the electrical outlets and an indication that an electrical contractor should examine your wiring. Oftentimes, homes are renovated several times without any electrical wiring updated. Yet, this is a part of the house that can cause huge problems if it isn’t kept up-to-date.

Outdated circuit boxes
When a home hits the 40-year mark the biggest area of electrical concern is the circuit breaker box. Zack Israel, owner of Mike Electric, says that when the circuit box becomes outdated, “it doesn’t do what it’s supposed to do.” He says that as the house ages, the brand of the circuit box becomes obsolete “and today, a new generation of improved boxes is being installed.” Israel cautions homeowners about the danger of not replacing an old and outdated circuit box. “If the breaker doesn’t trip then the wire might melt and cause a fire,” says Israel.

Kitchen wiring upgrades
An area of an older home that typically needs upgraded wiring is the kitchen. “The kitchen is an area that always needs to be upgraded after 40 years. Several decades ago we didn’t have microwaves and all the appliances that we have today,” says Israel. He says that what can happen if the kitchen wiring isn’t upgraded is that when appliances are used, the circuit breaker trips or, even worse, it doesn’t trip at all. “So the kitchen is an area that you want to upgrade and bring more power to it,” he says.

The electrical code requires two circuits of 20-amps, 120 volts for GFCI (Ground Fault Circuit Interrupter) receptacles for the kitchen/eating area. However, more might be necessary depending on appliances being used.

Heavy-duty appliances need dedicated outlet
A common problem for homeowners occurs when there isn’t proper distribution of the electrical circuits. Israel says homeowners often don’t understand this. “Let’s say for example that [depending on the weather] a homeowner tries to use a portable air conditioning system or heater and plugs it into just any plug – and boom! there’s no power – it trips the circuit. This is common. People don’t know that they need a dedicated circuit for that kind of appliance,” says Israel.

Wire insulation cracks
Another big problem for older homes is that electrical wiring insulation cracks. “Especially in the ceiling lights, the heat from the light rises into the box and causes the wiring insulation to crack,” says Israel. When homeowners consider tackling the task of rewiring their home they’re often overwhelmed by it—feeling like it will be too expensive and too much trouble. While it is true rewiring can be a major renovation that, in some cases, even means the homeowner must leave the home for a period of time – due to electricity needing to be turned off or just the inconvenience of living with workers in your home — the end result of peace of mind from knowing your electrical system is working properly and no longer at risk of causing a fire – (a major concern of home insurers) – is well worth the expense and any temporary hassles.

Written by Phoebe Chongchua as found in Craig Lilly’s Newsletter.

Cracked Foundation Wall

StructuralSupport — Mon, 26 Oct 2009 16:59:07 +0000

Cracks in foundation walls can be of no significance or a major structural defect, which can be expensive to correct. Proper evaluation is therefore very important to determine:
(1) If repair work is warranted and,
(2) Details for effective repairs.

As a licensed professional engineer, I am called in to evaluate cracked foundation walls frequently. Unfortunately, repairs for defective foundation walls can easily cost tens of thousands of dollars. However, much money can also be wasted based on incorrect evaluation by unqualified persons.

Water in the soil around a basement is often one of the factors responsible for cracked foundation walls. Water in the soil may also be the source of water leaking into a basement. However, cracks in foundation walls are generally not the primary cause of water leaks. There are also other potential causes of water infiltration into a basement. Therefore, although increased pressure from water (against foundation walls) is relative to this discussion, the topics of water infiltration (leaks) into a basement and waterproofing should be discussed separately.

Much information provided online about this topic (cracked foundation walls) is grossly misleading or totally incorrect. Many descriptions tend to be vague, confusing or off-topic. Examples of incorrect online information are provided at the end of this discussion.

DISCOVERY OF FOUNDATION CRACKS
Cracks in foundation walls typically occur within several years after a house is built, although there are exceptions (such as tree roots). Owners often do not notice cracks until many years after initial formation. This is especially the case in dark basements. The most dangerous situation is when cracks occur in foundation walls when the basement is finished. Although catastrophic failures are relatively rare, cracked-wall conditions can progress over time to total foundation wall failure without anyone seeing the progression.

Cracks in foundation walls often become a major issue when discovered by a home inspector during a pre-purchase inspection. Although the owner usually contends a cracked wall has been that way “forever”, a buyer tends to become concerned when confronted with a warning in the inspection report. Homeowners selling a house often attempt to cover-up foundation cracks by painting the wall or filling cracks with flexible caulking. A qualified, experienced home inspector should highlight any such attempt in the home inspection report.

BASIC TYPES AND CAUSES OF CRACKS
Cracks are generally considered vertical, horizontal or “diagonal” (sloped), even though most cracked-wall conditions include all three categories.

Narrow vertical cracks are most often caused by minor settlement or normal shrinkage. Such cracks are not structural defects. Wide vertical cracks (such that the thickness of a 25-cent quarter coin can be inserted) may be caused by significant settlement problems that require detailed engineering inspection and evaluation. In concrete walls, you will almost always find numerous, very narrow (“hairline”) vertical cracks. These cracks are caused by normal shrinkage of concrete and are not a structural defect. Foundation walls built with concrete block (often, and incorrectly, described as “cinder” block) are much more likely to be cracked than solid concrete walls, especially if the block wall is constructed of 8-inch block.

Horizontal cracks are much more of a concern than vertical cracks, especially in block foundation walls. Foundation walls must of course support the vertical weight of a building. Foundation walls around a full basement must also resist inward (lateral) pressure from soil against the wall. If soil (backfill) becomes saturated with water, inward pressure can easily overload a block wall, resulting in cracks. Excessive inward lateral pressure against a block foundation wall all too often causes horizontal cracks in mortar joints. Telltale sign of excessive lateral soil pressure is a horizontal crack, about mid-height of the wall. Towards the ends of a straight foundation wall segment (near corners), horizontal cracks transition into “step” cracks, which are short vertical and horizontal cracks.

The building code includes standard limits for height of “unbalanced” backfill soil against a concrete block or plain concrete foundation wall. For an 8-inch hollow concrete block wall, height of backfill (above basement floor slab) is limited to 4 feet. Block foundation walls often remain cracked for many years without any obvious additional cracking or inward movement (bulging). However, once a horizontal crack occurs, the structural integrity of the wall is greatly reduced. If soil backfill becomes saturated during periods of heavy rainfall, cracks can increase or, in the worst case, the entire foundation wall can collapse into the basement.

Roots from large or even moderate size trees near a foundation wall can easily cause major problems with block foundation walls. Roots tend to grow towards foundation walls because water accumulates along the wall.

BASIC REPAIR METHODS – HORIZONTAL CRACKS
Cracked foundation walls can be permanently repaired, without complete replacement, as long as inward movement is not excessive, even though evaluation of excessive movement is somewhat subjective. The key issue is whether the wall can continue to provide vertical support for the house without risk of severe damage in the even vertical loads are increased. Inward movement is typically measured relative to base of wall, using four-foot carpenter level or plumb string-line. Maximum inward movement (deflection) usually occurs at the horizontal crack and near mid-height of the wall.

If inward movement of a cracked foundation wall exceeds 1-1/2 inches, or if a hinge has occurred at the horizontal crack, consideration must be given to complete replacement of the wall. Cost for replacement is typically much greater than cost of bracing. Therefore, having repair work performed before inward movement increases is essential to minimizing repair costs. Traditional repair methods involve bracing the foundation wall with steel post-braces or reinforced block piers. Steel post-braces may be less expensive than piers, which must be placed on a concrete foundation (footing). However, piers often provide a better finished appearance.

Steel post braces must be securely connected at base and top, which is all too often neglected if braces are not designed by a qualified engineer. Steel reinforcing bars have successfully been installed (grouted) into block walls to provide adequate strength to resist soil pressure. However, this method is highly dependent on quality of workmanship. Inspection is effectively impossible once bars are in the wall. Installation of bars also requires extensive removal of inside face of block wall, which can cause damage to unseen parts of the block.

In recent years, more exotic repair methods have been developed, such as tiebacks and carbon-fiber strips. Although these methods have been used successfully, there have also been failures, as there are with any relatively new technology. Careful application of newer methods is therefore warranted.

MISLEADING AND INCORRECT ONLINE INFORMATION
Examples of errors with online information, discussed below, demonstrate why it is important to obtain information about foundation wall problems from qualified professional engineers.

INSPECTAPEDIA
Currently (10-18-09) the top link obtained from a Google search of “cracked foundation wall” is an advertisement for inspection services on the “InspectAPedia” web site.

http://www.inspect-ny.com/structure/FoundationCracks.htm
Excerpts from a “book” (that apparently is not available other than online) provide some detailed information about evaluating cracked foundation walls. At end of the web page, the apparent author (Daniel Friedman) includes a long list of persons without any clear description as to the intent. The apparent intent is that these persons are contributors or perhaps fact-checkers.
Statement of qualifications notes that Mr. Friedman is an “Educator, author, Building failures researcher” and a “Consultant specializing in construction & environmental testing & inspection.”

Although much information presented is valid and useful, some claims are confusing and misleading, as noted with the following two examples:
(1) Claim that the location (within height of wall) of horizontal cracks explains the reason for the cracks are overblown. This claim is simply not reasonable considering the wide variety of factors that can result in horizontal cracks, including workmanship, materials, and various sources of loads over long periods of time. One major source of cracks (tree roots) is completely ignored.

(2) A diagram included with “Repair Methods for Bulged Foundation Walls” is grossly incorrect. Base of the vertical steel channel is shown above the floor slab, without any connection. This is a major mistake. Base of any such vertical brace must have secure connection to the floor slab to resist horizontal force, which is greatest at base of the brace.

ASK THE BUILDER
An example of misleading and incorrect information that you might trip over online (as of 10-18-09) is the following from the “Ask The Builder” web site:

Crack Appearance: Horizontal Crack in a foundation wall. Commonly seen in concrete block walls. Crack is usually 4 to 5 feet off the floor.

Possible Cause: Poorly designed foundation wall. Wall is actually a retaining wall trying to hold back dirt from falling into basement. Can be fixed with beams or helical piers.

Description of the crack is not complete since horizontal cracks in block walls always occur in one or more horizontal mortar joints. Comment about “usually 4 or 5 feet off the floor” is not correct. Most horizontal cracks occur at or below mid-height of a block foundation wall, where the largest flexural tension stress occurs. The vast majority of residential block foundation walls are less than 8 feet high, such that height of horizontal cracks is generally less than 4 feet above basement floor slab.

Horizontal cracks can be caused by defective construction as well as defective design. While the “retaining wall” comment is correct and useful for understanding, this is true of any foundation wall, not just a wall with a horizontal crack. Most important however is that the suggested repair methods (“beams or helical piers”) are grossly inadequate and incorrect. A beam is generally a horizontal element. A foundation wall with horizontal cracks must be braced with vertical elements, against the wall. “Helical piers” (a type of steel pile) are used only to underpin a foundation wall when settlement (downward movement) is the problem. Helical piers (also known as “auger piles”) are not useful in any way to repair a foundation wall that has been cracked due to inward soil pressure.

For more articles by this author, please go to Helium.com

John F Mann, PE
Structural Support
1212 Main Street, Suite 2
Belmar NJ 07719
732-556-6080
jmann77@optonline.net

Fire Prevention

RoofingandMore — Mon, 19 Oct 2009 15:08:12 +0000

Every year, U.S. fire departments respond to approximately 399,000 fires. Fires kill nearly 4,000 people annually, including about 100 firefighters lost in the line of duty. Fires injure many more people and result in hundreds of millions of dollars in property damage. These statistics are made even more tragic by the fact that many fires could have been prevented.

Fires can be prevented with a little common sense. Review these important tips about fire safety.

Cooking accidents are the leading cause of house fires. Never leave cooking unattended. If you cook on a gas stove with an open flame, don’t wear loose sleeves as these can drag into the flame.

Loose clothing, dish towels, and curtains are a danger around flame sources, including candles. Use care with open flame sources.

Place fire extinguishers near ALL potential fire hazards, like stoves and fireplaces.

Keep clutter away from heaters, water heaters, furnaces, stoves, and ovens. Clean lint regularly from your clothes dryers.

Fire alarms cut the danger of being hurt or killed in a fire by 50%. Two-thirds of all fire deaths occur in homes with no working smoke alarms. Test fire alarms once a month. Replace batteries at least once a year. Install fire alarms in or near every bedroom and on each level of your home, including the basement. If you have an oil- or wood-fired heating system, also use a carbon monoxide alarm.

Devise an escape plan in case of fire. Designate two exits from every room. Practice regularly. Put fire ladders in all rooms above ground level. Teach everyone the “Stop, drop, and roll” technique.

Teach kids that matches, lighters, and candles are not toys. If you suspect that a child is playing with fire, check for telltale signs, like burned matches under beds and in closets. Store matches and lighters in a secure spot.

Electrical Safety

ArdilaConstruction — Wed, 29 Jul 2009 11:24:34 +0000

Although it seems pretty common sense to do so, several people, including professional electricians do not adhere to all electrical safety. The most common is working on “live” wires.

Below are a few tips to keep you safe while working on any electrical projects:

Never work on any live circuit, fixture, receptacle, or switch.

Always shut off power at the main disconnect before changing a fuse.

Always shut off power to the circuit before repairing or replacing a switch, receptacle, or fixture.

Always tape over the main switch, empty fuse socket, or circuit breaker, empty fuse socket or circuit breaker when you’re working. Leave a note there so no one will accidentally turn on the electricity. Keep any fuses you’ve removed in your pocket.

Always check that the circuit is actually dead before you begin working on it. Use a circuit tested or voltammeter.

Always unplug any appliance or lamp before repairing it.

Stay Safe.

How to Repair Roof Trusses

StructuralSupport — Fri, 17 Apr 2009 12:00:48 +0000

Prefabricated wood roof trusses have been used in the US for more than 30 years in house construction. Builders often use trusses to reduce costs compared to site-framed roof framing. After the house is built, roof trusses are often modified when home owners and contractors make alterations. Many such modifications are not made correctly. Although damage often does not occur, for reasons described below, the potential for major problems remains.

In many cases, improper truss modifications are found by a municipal inspector, or home inspector for a prospective buyer, after a house is put on the market for sale. Remedial work is then usually necessary to allow the sale to proceed. Concepts for the most common modifications are discussed below. A qualified professional engineer should be consulted for all truss modifications.

BASIC PRINCIPLES
Roof trusses are an assembly of wood pieces (most often 2x4s) connected together with steel plates to form a unified structural member. Within the industry, a truss is referred to as a “component”. A truss serves the same purpose as any beam, which is to support loads across open space. This basic principle applies to roof trusses, even though the shape is obviously different than a “straight” member (such as a 2×12) that is more recognizable as a beam. The truss does behave quite differently than a solid, straight beam. Each member (piece) of the truss must resist force in tension or compression, parallel to the length of the member.

The key principle to understand, relative to modifications, is that every member of a truss is essential for adequate performance. If a truss member is cut or removed, the entire truss becomes defective, unless remedial work is performed to properly redistribute loads around the modified part of the truss. Cutting or removing a truss member has essentially the same effect as making a cut through the entire depth of a solid beam, such as a 2×12 floor joist. Roof trusses typically require lateral bracing, perpendicular to the plane (length) of the truss. This bracing should not be removed, especially for trusses with relatively long “web” members.

TERMINOLOGY
To understand discussion of roof trusses, it is necessary to understand standard terminology. Reference to a truss diagram is of course useful. The Wood Truss Council of America (WTCA) provides basic information, including diagrams, on their web site; http://www.sbcindustry.com.

Understanding the following terms is necessary to clearly discuss residential roof trusses;
Joint Location – where truss members intersect.

Truss member – Individual piece (segment) between joints.

Long chord – members may consist of two or more segments joined by light-gauge steel splice plates.

Bottom chord – One or more members that form the bottom of the truss. Bottom chord members are most often horizontal. However, for some applications, such as a “cathedral-type” ceiling, bottom chord members may be sloped.

Top chord – One or more members that form the top of the truss, which also forms the roof surface. Top chord members are most often sloped. For the simple gable (“A”) roof, there will be two lines of top chord members; one for each roof slope.

Web Truss – member between bottom chord and top chord. A web member is almost always vertical or sloped.

Connection plate – Light-gauge steel plate used to connect the various wood members. Plates are installed at the factory. It is not practically feasible to install the standard connection plates at the site.

TYPICAL TRUSS MODIFICATIONS
Roof trusses are most often modified to install an opening in the ceiling under the roof. The ceiling is attached to the underside of the truss bottom chords, which also support any attic floor that may have been installed. One typical reason for making an opening is to install folding stairs to provide access to the attic space. Almost all residential roof trusses are spaced at 24-inches. Clear space between bottom chords of adjacent trusses is then 22-1/2 inches. If the length of the opening (for folding stairs) is parallel to the trusses, the frame for the stairs if often too wide to fit within the available space between trusses. Therefore the bottom chord of one truss must be cut.

In some cases, the only way that the stairs can be useful is to install the length of the stair opening perpendicular to the trusses. For this orientation, the bottom chord of several trusses may have to be cut. As noted above, when a truss member is cut or removed, the truss is no longer capable of supporting load across the full span of the truss, between ends.

EVALUATION
Before cutting any member of a truss, an evaluation should be made to determine how the cut truss will be supported and reinforced after the modifications. Of course in many cases, this evaluation must be performed after the truss has already been cut. First step is to determine if there may be interior walls that can be used as a bearing wall, to support the modified truss. In many cases interior bearing walls are available, especially when new folding stairs are installed above a hallway. A bearing wall must have adequate support under the wall. A continuous “load path” must then be available so that all loads supported by the bearing wall can be safely transferred through the structure, all the way down to foundation elements.

CUTTING BOTTOM CHORD – WITH INTERIOR BEARING WALLS
If a bearing wall is available for each segment of the bottom chord (that was cut), each segment can usually be supported on a wall. However, some reinforcement of the truss may be required, such as installing a new 2×4 or 2×6 against the bottom chord. New web members may also be required, with adequate connections made by plywood “gussets” and either nails or wood screws.

CUTTING BOTTOM CHORD – WITHOUT INTERIOR BEARING WALLS
In the event that interior bearing walls are not available (for both segments of the cut bottom chord), the following work is required;
1. Install a header across each end of the truss bottom chord that has been cut. This will require two headers, which fit between adjacent full-length trusses that have not been cut.
2. Install light-gage steel joist hangers or other hardware to connect cut end of the truss bottom chord to the header.
3. Reinforce the full-length adjacent trusses as necessary to support new “point” load from the headers. Structural analysis by a qualified professional engineer is required to determine the extent of reinforcing necessary. If possible, analysis should be performed by the truss manufacturer.
4. Install joist hangers to support each end of each header, at the reinforced full-length trusses.

Installation of headers is practical when only one or two trusses have been cut. However when several trusses have been cut, it may not be practical to reinforce the full-length adjacent trusses due to the relatively large point loads imposed by the long headers.

CUTTING TOP CHORD
When a top chord must be cut, perhaps for a new skylight, repair requirements are similar for the case of cutting the bottom chord. However, installation of new web members is more likely to be necessary.

CUTTING WEB MEMBERS
When a web member must be cut, the truss can often be modified by installing new web members near the location of the cut web. However, when this is not feasible, much more extensive reinforcement of the truss will be required.

REPAIR OF DAMAGED TRUSS MEMBERS
In general, it is always possible to repair a damaged truss member using relatively simply methods. Damage can occur for many reasons, including impact during construction. Many trusses that are damaged by construction workers are not repaired by the builder. Essentially, another wood member must be installed alongside, and securely connected to, the damaged member. More difficult is repair of damaged steel connection plates. Much larger plywood gusset plates often must be installed to provide the same connection capacity.

For more articles by this author, please go to Helium.com

John F Mann, PE
Structural Support
1212 Main Street, Suite 2
Belmar NJ 07719
732-556-6080
jmann77@optonline.net

Changing Electrical Switches

Details — Wed, 08 Apr 2009 17:43:31 +0000

Changing a wall switch can be pretty simple, but having some basic knowledge of the different types of switches and how to replace them can be most helpful.

Types of switches
A Single-Pole switch controls a light/receptacle in one location only. The switch has two screws of the same color.

A Three-Way switch operates in pairs to control a light/receptacle in two locations. The switch has two screws of the same color (either brass or silver), and one screw of another color (either copper or black). This copper or black screw is called the common terminal screw.

A Dimmer switch is wired as the single-pole switch and have either terminal screws or lead wires.

CAUTION: Before working on any switch, make sure the power to that switch is SHUT OFF.

Replacement Tips
Read ALL information embossed on the back of the new switch, which should have the same amp and voltage ratings as the old.

Pay attention to marks on the replacement switches, and make sure they match up to your existing switch. If your home’s wiring is aluminum, use only replacement switches marked CO/ALR. Replace unmarked switches and switches marked CU/AL with switches marked CO/ALR. Don’t backwire switches to aluminum wiring, attach aluminum wires to terminal screws only.

Replacing a Single-Pole Switch
Remove the cover plate.
Remove screws and pull out switch carefully.
Unfasten the wires.
Loop the stripped wired ends clockwise around the terminal screws on the new switch.
Tighten the terminal screws with a screwdriver (hand tight).
Replace the switch back into the box so you don’t crimp the wires.
Replace the screws securing the switch to the box.
Replace the cover plate.

Replacing a Backwired Single-Pole Switch
Remove the cover plate.
Remove screws and pull out switch carefully.
Using a small bladed screwdriver, press the screwdriver into the release slots on the back of the switch, then pull wire out of slots.
Push in the stripped wire ends into the slots on the new switch.
Replace the switch back into the box so you don’t crimp the wires.
Replace the screws securing the switch to the box.
Replace the cover plate.

Replacing a Three-Way Switch
Remove the cover plate.
Remove screws and pull out switch carefully.
Make sure you label the wire to the common terminal screw with tape.
Install the new switch, attaching the labeled wire to the common terminal screw (black or copper.)
Re-connect each remaining wire to either of the remaining screws.
Replace the switch back into the box so you don’t crimp the wires.
Replace the screws securing the switch to the box.
Replace the cover plate.

Installing Dimmer Switch with Terminal Screws
Remove the cover plate.
Remove screws and pull out switch carefully.
Loop the circuit wires clockwise around the terminal screws on the dimmer.
Replace the switch back into the box so you don’t crimp the wires.
Replace the screws securing the switch to the box.
Replace the cover plate.

Installing Dimmer Switch with Lead Wires
Remove the cover plate.
Remove screws and pull out switch carefully.
Connect the circuit wires to the dimmer’s lead wires, twisting them together.
Screw on wire nuts and insert the dimmer in the box.
Replace the switch back into the box so you don’t crimp the wires.
Replace the screws securing the switch to the box.
Replace the cover plate.

Tips on how to strip electrical wires
Use a utility knife or penknife to strip insulation off the ends of the wire.
Use the knife blade to cut through the insulation all the way around, then pull the insulation off the wire.
Be careful not to nick the wire when you cut as a nicked wire breaks more easily.
If you do nick the wire, just start over and cut the wire back to the nick.

For the best results, purchase a wire stripper at your local hardware store.