Category Archives: Energy Code

Quality Installation and Maintenance of HVAC Equipment

The news this month has multiple stories about Heating and Air Companies being very busy with units not cooling or not cooling enough.Screen Shot 2016-06-24 at 8.49.56 AM Driving around town, I see most of these contractors have a sign out front looking for help. The wait time is up to two weeks.  In the 7 homes I’ve been in this week.  One had no working AC, one home was on it’s last legs, and two other homeowners were very concerned. For the 1st time in 7 years, I’m getting calls from my website asking if I can fix their AC unit.

This morning I found a report on HVAC Problems, Problem Identification and Repair.  I have scanned this 27 page report and these are the things that jumped out.

Background:  California has some of the toughest energy requirements for buildings, both new and remodeling of existing buildings. These is a direct result of the problems they had 15 years ago, with not enough electricity.  They resulted to black outs, (Utilitys were allowed to shut off electricity to various geographic areas).  and brown outs, (Utilities were allowed to provide only part of the electricity needed to a geographic area).  Both are not good.

These energy codes are generally referred to as Title 24.  A large part of the work in California the last few years has been testing and measuring how well the requirements are being met.  This report is just one small piece of that process.

Title 24 refers to the problems, their identification and repair as “Fault Detection and Diagnosis” or “FDD”

Screen Shot 2016-06-24 at 8.51.18 AM

The Report was working on the answers to these questions

  • Is FDD worth the investment, and what is the savings potential?
  • How effective are available FDD methods and what do they cost to implement?
  • What training is needed for effective FDD and is it being provided?
  • Are codes and standards working?
  • What are the major gaps and how can they be addressed?

This particular session and reporting was limited to:

 

  • System Types–new and existing residential only
    • Air conditioners
    • Heat pumps
    • Furnaces and air handlers
  • Fault Types
    • Low airflow
    • Refrigerant system charge, restrictions, and contaminants
    • Mechanical and electrical faults and faulty installation
  • Repair vs. Replacement Issues
    • Cost-effectiveness of FDD
    • Replacement refrigerants for R-22
  • Human Factors
    • Training and quality of maintenance
    • Homeowner knowledge and expectations.

The reporting included tests applied with standard AHRI methods. The tests were designed to determine the impacts on efficiency and capacity of a variety of conditions, including:

  • Airflow of 250 cfm/ton reduced energy efficiency ratio (EER) by 12% and has the potential to produce a false overcharge diagnostic due to freezing of the coil (the asterisk denotes an unofficial EER)
  • Liquid line restrictions (e.g. due to clogged filter-dryer or metering devices) reduced EER by 30% to 36% for non-TXV and TXV systems respectively
  • Only 0.3% Nitrogen in the refrigerant reduced the EER  by 18% with no TXV and 12% for the TXV-equipped system

Discussion pointed out that California Title 24 charge verification methods, which only measure superheat (for non-TXV) and sub-cooling (for TXV) systems, and ACCA Standard 4, for which only 3% of the procedures are related to energy performance. Also covered were  how improperly maintained vacuum pumps, test instrument error, and poor service practices such as use of rules of thumb contribute to the introduction of non-condensables, improper charge, and other faults.

John Proctor, PE presented a case for making improvements to California’s Title 24 standards, John worked with a team to inspect a large number of recently built homes to identify HVAC installation and performance issues. He began his presentation by defining an “incremental effectiveness ratio” that divides benefits of maintenance by the incremental cost to diagnose, repair, and ensure quality, which is fundamental to the question of the value of HVAC service. He proceeded to show a series of graphs from his experience and other studies that illustrate the deviations from the ideal for airflow, charge, duct leakage and efficiency, and non-condensables, as well as the incidence of occurrence of these defects.

For example, his graphs show:

  • 50% reduction in airflow reduces EER by 25%.
  • A refrigerant charge that is 70% of the recommended charge reduces EER by about 55%.
  • Leaving Nitrogen in the line set and coil at 20 psig before charging with refrigerant reduces the sensible EER by about 45%.
  • From his 2003 survey, more than 60% of the houses checked failed on refrigerant charge, airflow, and duct leakage, and more than 95% failed overall.

Many of these issues result from a lack of training and a lack of follow up by supervisors.

They had some specific things that could be done by builders, HVAC Contractors and home owners to ensure these items do not get missed.

I will read the report in more detail and have further comments.

You may read the entire report.

Medical Study Shows Green Homes Decrease Illness

One of the benefits of buying and living in a green home has always been health related. Energy Efficient and sustainable builders have always taken care to keep water out and to seal up air leaks.  One of the effects is to lower your energy bills. Another is to improve the health of those living in the home.

No Flashing Window

The picture above is a window that was not flashed properly. Water was going into the wall. When you have water and wood together, you get mold.  Many new homes do not have this feature. Remember, there is no legal requirement to install insulation or other healthy features in a home in Wichita or Sedgwick County.

Now, US News and World Report’s Health Day column, written by Amy Norton covers a study in Boston.  She covered the research report in the American Journal of Public Health.

“Researchers found that children living in Boston’s newer, greener public housing had fewer asthma attacks, hospital visits and missed school days, compared with their peers in standard public housing. 

Adults, meanwhile, were less likely to report symptoms consistent with a condition called “sick building syndrome” — which include dizziness, headaches, nausea and eye irritation.”

Buying a home that has green features, such as Water Management Details, Air Sealing, and a Planned Fresh Air system is a big part of the Green Home that creates these benefits. You can find green homes, featuring these benefits, in and around Wichita. Some builder’s choose to have their homes certified to a Voluntary Standard such as Energy Star or Zero Energy Ready or or NAHB Green, or Eco Select.  A certified homes have these features verified by someone other than the builder.

So as the New Home market is growing in the Wichita Area, ask your builder about these features.  Don’t accept the answer that it is not needed, or this is what everyone else does. This is about the health of your family.

Read the entire article

 

Buying an Energy Efficient Home

HomePOHThe Annual Spring Parade of Homes is on the last week in the Wichita Metro Area.  There are some great homes out there. Lots of amenities to consider. Everyone has their own lifestyle and looks for a floor plan to fit. They all have their sense of taste and can look at the colors, finishes and visual effects.

POH_S15Every builder says they build an energy efficient home. Energy Efficiency is built in behind the walls.  It is usually not seen.  Energy Efficiency is about people and how they install the items that create the efficiency.  The specific items are less important then the way they are installed. Generally, the manufacturers install instructions must be followed.

Wichita – Sedgwick County has not adopted any code provisions for energy efficiency in new homes.  It may be legal to build a home with no insulation, but is that a wise decision? No one thinks so.  So how much is enough and is it installed correctly?  In this area we are reliant on the free enterprise approach energy efficiency in new homes.

Phoenix, AZ has an energy code, yet the free enterprise market based system has upped the game for buyers.  Here is a recent article in the Phoenix Newspaper about how a home buyer can see what is behind the walls.

Arizona-Republic-Features-of-ENERGY-STAR-HERS

New Efficiency Standards for Hot Water Heaters

The National Association of Home Builders has condensed the DOE page on the new Efficiency Standards for Hot Water Heaters. The good news is if you buy the unit, you can install it, until existing stocks are used up. There are also some alternatives in specifying and installation you can consider.

Elec DHWNew residential water heater energy-efficiency standards that go into effect April 16 will require changes to the installation of many residential water heaters. Most water heaters with a capacity of 55 gallons or less will require more installation space, and those larger than 55 gallons in capacity will see additional, more significant changes. However, products manufactured before April 16 can still be bought and installed after the changeover date.

These new efficiency standards will require much higher Energy Factor (EF) ratings for larger water heaters, making a huge impact, especially on how these types of water heaters are manufactured, distributed, installed and/or vented.

PV DHWThe more common-sized water heaters of 55 gallons or less will likely be larger by roughly 2 inches in height and diameter to account for the additional insulation needed to meet the new standard. This may require builders to account for the increased size in their design.

It is expected that replacement water heaters installed in closets will present the biggest problems: They may require installing an applicance with reduced water capacity, selecting a much taller tank of the same diameter or a switching to a tankless water heater if space does not allow for a simple change-out.

As more information is available from manufacturers and the federal Department of Energy, NAHB will update this page.  Continue Reading

Indoor Air Quality Evaluations

The quality of the Indoor Air of our homes and offices is an important part of our health and comfort.

There is not much sense in putting a lot of good insulation into a building if it is:

  • Not Structurally Sound
  • Not Healthy

What types of things can be done to improve the Indoor Air Quality of any home or property?

  1. The immediate environment of the structure must be kept separate from the inside.
  2. The required fresh air that is needed, in every one of our buildings, should be filtered and otherwise treated for comfort and to remove pollutants.
  3. The pollutants that are created during the normal operation of our building must be eliminated, removed, replaced, diluted or neutralized.
  4. Moisture in any form must be controlled , and then removed avoiding any accumulation.
  5. Any and all accumulations of moisture damage or animal infestation must be cleaned up and damaged building components replaced.
  • A Full Indoor Air Quality evaluation must address all of those concerns.
  • Full interior visual inspection
  • Full exterior visual inspection
  • Testing of the building enclosure to ensure the outside stays outside
    • Infrared Evaluation as part of the above testing
  • Inspection of HVAC Duct Work and systems that move air.
  • Combustion Safety Inspection on open combustion appliances
    • Moisture, Carbon Monoxide, N02, SO2 and others
  • Infrared and other testing for moisture accumulations.
  • Sample Collection of suspended and/or deposited material that are potential pollutants or irritants.
    • Examination and Evaluation by a certified Microbiological Laboratory of these samples.

This evaluation is typically completed in two visits to the home or business. Level I Evaluation and Testing is non-destructive and not invasive.

Level II Evaluation and Testing involves invasive inspections. These may be as simple as drilling a few holes for visual inspection or sampling. It may involve removing obviously damaged building material, that requires replacement, for example wet drywall.

Contact The Energy Guy for further information about an Indoor Air Quality Evaluation.

Who Is Building an Igloo in Wichita?

It all started on Twitter. @AIAWichita @moongodess316 and I had some fun over building an Igloo.

Igloo1

I saw this Tweet and immediately thought of a quote from Dr. Joseph Lstiburek: “The Igloo was the First Passive House.” Joe is an engineer by training and has been working with buildings, insulation and energy use for over 30 years. His Building Science Corporation, based in Massachusetts, conducts research and is one of the best sources of verified information on building energy efficiency in buildings.

So I tweeted back.

Igloo2

What is the difference between a Passive House and a regular house? What is the buzz all about?

Strawbale

When you build a home you can use lots of insulation to reduce the amount of electricity and gas to heat and cool the home.

GSHP Diagram

You can use a lot of high tech equipment to reduce the amount of electricity and gas to heat and cool the home. You can also do both.

PHIUSThe Passive House was developed in Germany, so you see it referred to at times as Passiv Haus.

We know that insulation works and that more insulation works better. As the cost of electric and gas goes up, it makes financial sense to add insulation to a home or business. In 2000, the local cost of Electricity was 8 – 9 cents, the recommended level of attic insulation was R-30. Today the cost of electricity is 12 – 13 cents and the recommended level of insulation is R-49.  Both have increased about 1/3 in 1 years. We also know that air movement, cold drafts, makes people uncomfortable and causes insulation to not work as effectively.

Round Metal TubeThe sources of air entering a home are usually related to corners. Since we like living in buildings that have square corners there are a lot of them in a home. Windows do not usually cause air leakage. How they are installed can cause air leakage. The age or the quality of the window does not seem to matter when installation mistakes occur.

PHIThe primary requirements for a passive ouse certification are based on Energy Usage and creating a structure that needs very little energy for heating and cooling. These standards are effectively summarized with these two limits.

  • Total primary energy (source energy for electricity, etc.) consumption (primary energy for heating, hot water and electricity) must not be more than 120 kWh/m² per year (37900 btu/ft² per year)
  • The building must not leak more air than 0.6 times the house volume per hour (n50 ≤ 0.6 / hour) at 50 Pa (N/m²) as tested by a blower door.

In our Twitter Conversation, Angee McBustee tweeted a question about how is building a igloo in Wichita. Then I responded with the offer to run the blower door test. As you can see from the primary requirements the Blower Door result is very important to a passive house.

Igloo4

How good is a Blower Door Test of 0.6, as required by Passive House? Energy Star New Homes require a Blower Door Test of 5.0 or less. New homes in Wichita routinely test around 4.0. In the blower door testing, lower is better.

For standard construction, I have tested several homes at 1.0. There is one home that I have tested with a lower result. A custom home in Butler County is under construction. They had me do a Blower Door test after it was sheathed. No insulation, no drywall. The test result was 0.62. We were able to find several leaks using biometrics and the infrared camera. That was last September. I returned in December to test it a 2nd time, the results were so low, that I didn’t have the right test equipment to measure the result. I would estimate it to be in the 0.30 range. I now have the equipment to test a home like that.

In February, I have been accepted for training and certification as a Passive House Rater/Verifier. Christine is building the home in Butler County, I want to thank her for the push to obtain this certification.

In the Twitter Conversation, AIA Wichita came back and said they were posting an information tweet.

Thanks to Angee and AIA Wichita for a nice idea for a Blog Post.

What Counts? Product A or Product B

Blower Door Testing & Weather Resistant Barrier

Tyvek TopThe practice of covering sheathing with asphalt impregnated papers has given way to the use of synthetic fabrics, known as house wrap; or spray on coatings. There are factory applied coatings on some brands of sheathing and some types of coatings are field applied. Along with the discussions of fiberglass / cellulose in the insulating of homes, there has been plenty of discussion about the merits of one form or another of WRBs.

As with any step in the building process, I believe it is less about the product and more about the people. Products that are hard to install will be less successful then others. Installers that are not properly trained; work that is not verified in some manner can defeat the proper performance of the best products.

WRBWhat does the WRB do for a home. First it provides a drainage plane behind the siding to divert rain and other weather related moisture from wetting the sheathing. Second, when all manufacturers install instructions are followed it can act as an air barrier, reducing infiltration. For the house wrap type fabrics, this means properly lapped, using capped fasteners, and then taped. Finding house wrap installed according to manufacturer’s install directions is rare.

When all three of these directions are not followed, not only are the potential qualities of an air barrier not present, the potential for water to run behind an uncapped fastener, or an incorrectly lapped joint, which is also untaped. Repeated wetting of the sheathing over time, will eventually result in rot and the accompanying problems.

Country HollowA local Wichita Home Builder, G.J. Gardner has just finished two homes based on the same floor plan. These homes went through the independent verification process involved in obtaining a HERS Rating. These homes utilized the same sub-contractors and types of insulation. The only difference in construction was the use of a job site applied spray on WRB, in place of a house wrap type fabric.

One part of this verification process is a Blower Door Test. This test simulates the effects of a 20 mph wind on all sides of the home at the same time. Blower Door testing has been completed on homes since the late 1970’s. Energy efficiency programs and building codes have consistently recognized the value of a Blower Door test on each home.

BlowerDoorThe value of doing a Blower Door test on each home is primarily to check the work of all subs has not compromised the Builder’s plan for an energy efficient home. Many existing homes, have a test rate of 7 – 12 or higher rates of air exchange during the test. The 2012 code requirement is 3 on this scale, and lower is better.

The use of 4×8 sheet goods for sheathing and other simple, and inexpensive techniques have brought the infiltration rates down. This reduces the cases of cold drafty homes, and significantly lowering the energy use of a home.

The Blower Door test can verify the quality of work involved with installing the WRB, specifically the degree of sealing of the outside of the sheathing. In the case of the two homes involved in this comparison, there was a change of 20% in the measured infiltration rates of the two homes.

In completing the Blower Door tests, we used the ANSI / RESNET published standard of a Multi-point test. These results were entered into a software package provided by the maker of the blower door, The Energy Conservatory, Below is a comparison screen between the two Blower Door Tests.

Tectite 2 Bldg Comp Data

I would like to thank Wade Wilkinson, with GJ Gardner of Wichita; his subcontractors and their technicians for building quality energy efficient homes. I enjoy being able to verify the quality of their work.

If you would like to see this home, it is currently in the Fall 2014, WABA Parade of Homes.  It is located in the Country Hollow Development.  Between Kellogg and Harry on 127th and East to Glen Hills Court, on the corner.  Find out also about the HERS Index earned by this home. It will save you operating costs on your Energy Bills.

Passive House Work in Wichita

In the last two weeks, two national groups that certify construction for Passive House Standards conducted their annual conferences.  PHIUS was held in Portland, OR; and PHI was held in Maine. Locally, I have completed the first of 3 planned Blower Door tests for a passive concept home under construction; discussed the planned construction with another builder to start later this year; and discussed passive building concepts with another builder planning his first homes next year.

PassivhausDarmstadtKranichstein-300The Passive House concept started in Germany, with construction starting in 1990 on several homes. In German, it is Passiv Haus,  PHI for Passiv Haus Institute.  The standards followed by this concept require an attention to detail in design and construction of the thermal enclosure.  Historically referred to as the envelope, the thermal enclosure involves the exterior bottom, sides and top of the structure.

  • Higher than commonly used levels of insulating material,
  • windows meeting specific standards and very
  • Effective work on air sealing
  • Attention to the Solar Orientation of the home to maximize the use of solar heat in the winter

PHIThis results in an extremely low energy bill.  How low? In the Wichita area, this would translate to an $88 – $110 annual natural gas bill, instead of $500 – $900 bills that I routinely see on Home Energy Audits.

The passive term comes from the idea of using insulation and construction techniques to create a significant energy savings instead of relying on fancy machinery to create that savings. Dr. Wolfgang Feist of Dahrmstat, Germany founded the Passiv Haus Institut in 1996.

Smith HouseThe passive house concept arrived in the US in 2003.  Katrin Klingenberg, a licensed architect in Germany, She built a home meeting these standards, 2 hours south of Chicago.

 

Most countries have a local organization that trains and certifies homes and commercial buildings to the Passive Standard. Yes, passive concepts apply to buildings other than homes. These groups train people to apply and measure the standards. They also review the reports on specific buildings and accept or deny actual certification for a specific building.

PHIUSIn the US, this organization has been known as PHIUS.  Passive House Institute, US. Ms Klingenberg has been the leading light of this group, which was founded in 2007.  There are some things in each country that differ from the original German model of Passiv Haus.

The experience of the professionals working with PHIUS in the US has resulted in some changes to how the concept is applied in the US. For example, the metric units used in the German (and most others in the world) have been translated to the Imperial units used in the US. The collaborative nature of US business groups has been essential to moving the passive concept from being used by a relative few to becoming a market force in the US.

Because these adaptations by PHIUS to the US market, were not acceptable to the original PHI, a divide between the approaches has occurred in the US.  It is mostly technical, and both groups agree the concept is still primary.  Effective building resulting in low energy use.

Some claims have been made that these concepts are two expensive for the US market. The original Passive House in Illinois was built at a 2003 cost of $94/ sf.  That is very favorable with current US construction costs. Since additional people are using the concept and the resulting products that manufacturers are producing, the mass production will bring some drop in costs.

If you wish to read more about the two national conferences for both the PHI and the PHIUS organizations that just finished, you may use these articles.

The 9th annual North American Passive House Conference (PHIUS)

Report from the Passive House Conference in Maine

I will keep you updated on activity in this area about Passive House building activity, as it progresses.  Three projects is a great start.  I’m glad that builders are willing to try new concepts and that home buyers are willing to step up and buy these homes.

In the introduction of this post, I mentioned a house under construction with the Passive House concept. I conducted the first of 3 Blower Door Tests last week.  This test was after the framing and exterior sheathing was completed.  Insulation, plumbing, electrical and trades had not started.  The second test will be in a few weeks after these trades have done their initial work and put holes in the enclosure.  Electric wires, plumbing, HVAC and other necessary conveniences of our lives will be installed in passive concept homes. The third test will be done at the end of construction.

The PHI/PHIUS standard for Air Infiltration as measured by the Blower Door Test is 0.60 –  The current 2012 recommended code requirement for this is 3.0 — Wichita/Sedgwick County does not have an energy code in place, but the Kansas City area does. They enforce a 5.0 standard.  Typical homes built from 1980 and prior are in a range of 10 – 38 from my testing.

The goal of the builder on this passive concept home was to reach 1.5 on this first test. Then using the Infrared Camera to find areas to caulk, and fixing the penetrations mentioned above, have the next test come in lower.

Blower Door62This test, actually came in at 0.62 —  almost the standard.  Much better than the expected 1.5 .   While the blower door was running, the Infrared found some places that could be fixed.  Dan, the carpenter, was right there with a caulking gun.  We also found some leakage with biometrics. A back of your hand that is wet, will show you extremely small amounts of air movement.  Most builders like to use expanding foam to seal the actual window to the rough opening.  We found some of these foamed openings were still leaking. Again the caulking gun was a good answer.

 

A Healthy Home Part 3 — Well Ventilated

Fresh AirA Healthy Home is well ventilated.  Everyone knows fresh air is important. This should be easy.  Well ventilated in more than just bringing in fresh air. The concepts are certainly easy, the details on the other hand take some thought and planning.  A new home ventilation strategy is fairly straight forward to design and implement. An existing home needs the input from the occupants and good analysis to address the problems. An effective ventilation strategy should address these issues in either new or existing homes.

  • Remove humidity, odors,, or significant problems from specific areas.
  • Remove stale, musty or other objectionable air.
  • Allow the occupants to choose fresh air sources that can be filtered or treated in other ways
  • Allow the occupants to choose to open windows when outside weather is appropriate
  • Allow the occupants to operate a system that can provide the amount of fresh air, to the appropriate places, in adequate amounts when needed
  • Provide fresh air when the outside air creates potential problems, such as Ragweed season or when other allergens are active
  • Provide air movement within the home, without the use of the expensive blower on the furnace or heat pump.
  • Allow minimal use of heating or cooling equipment during the shoulder seasons, when temperature changes are minimal, while keeping the home comfortable.

Billings QuoteHow much fresh air is needed?  Going back to the 1890’s, the number has been pegged at 30 CFM (cubic feet per minute) per person. This number was validated in a number of different studies and with the public health authorities in larger cities, dealing with large apartment buildings and recurring respiratory diseases.  I was pointed to the quote at the left by Allison Bailles. he located the original book on Google Books, page 20.

Beginning in the 1930s, research into changes in building techniques began to show the optimal number was closer to 15 CFM per person.  Some of the changes in construction included the increased use of forced air heating, moving from balloon framing to platform framing, increasing square footage, and the use of insulation in walls and attics. The formula changes from time to time and everyone has an opinion on details. The common point remains, fresh air is needed in every house.

Part of the Ventilation is removing air with a problem. Where is that?  Humidity is found in rooms that use hot water and basements.  Showers, tubs and cooking are the large sources of humidity.  The smells from food preparation and cooking can be very mouthwatering.  When the meal is finished and the refrigerator is full, the lingering smells become odors.  The answer is some spot ventilation in these areas. If your basement has a humidity problem, you can tackle that with a fitted sump pump cover to contain the humidity, and work to eliminate any water seepage.

vent fanSpot ventilation is a window that opens and an exhaust fan. The size of these fans is part of the formula that is specific to each home. The features of the fan are common to all homes.  It must be quiet. Builder grade fans are noisy. Noise in fans is measured in ‘Sones’. The Sone is a linear measurement of noise, compared to the decibels used by OSHA and others which is an exponential measurement.  Linear is better for quiet sounds, and decibels is better for loud noises. Fans should be less than 3 sones, and preferably less than 1 sone.  Reasonably priced fans are available that rate a 0.3 sones. A 1 sone fan is very quiet.

UnknownFans are certified for air flow and noise levels by the Home Ventilation Institute. HVI certification is very common and includes both the Sone rating and CFM rating.  When installing a fan, you must consider the duct losses that will occur in meeting the required air flow.   The rates for bathroom air flow  are 50 CFM, and 100 CFM for a kitchen.  Do not expect to buy a 50 CFM fan for a bathroom and connect it to 6 or 8 feet of duct work, and obtain 50 CFM.  I have measured 30 CFM routinely in these set ups.

Most people understand that various parts of their body are just a part of the whole.  If you start some type of therapy, there may be a side effect. Physical Therapy starts and you end up with some sore muscles, aha!  Side Effect!  Start a therapy for cancer and your hair may fall out, aha! Side Effect!  Your home works the same way.  Each part is just part of the whole. Change something, aha! What is the side effect?

House-System-imgAll of the items in the list above are part of the whole. For an existing home, some specifics of that house may indicate concentration on one or another of those areas.  A home built in the 1920’s will benefit from a different approach then a house built in the 1980’s.

A new home should have the ventilation system that meets the general points above.  The natural ventilation provided when windows and doors are opened, or the mechanical ventilation system that allows filtered and perhaps treated fresh air brought in from specific places and in specific amounts, allow the occupants to make the system work as they need.

 

This post is part of a Series on A Healthy Home

 

 

A Healthy Home Part 1a: How Dry is Dry? –

rain

Water in a house, Good Thing, Bad Thing?  Some places like the sink you expect to find water. Other places like the floor, water is a problem. Builders work hard to build a home so water says where it belongs.

RoofLook at the way the roof is installed!  The shingles are layered from bottom to top. They are also lapped over each layer. So water, will drain down the roof and off.  If water gets up under a shingle, the roofing crew has done some other things like roofing felt, metal valleys and flashing to do the job.

Look at the water run off the overhang in the top picture.  When it rains most of the water hits the roof, the overhang changes how much strikes the wall. Matt Risinger, a home builder in Austin, TX, tweeted this graphic recently.

Overhang

Do you think Matt builds homes with short overhangs?

SidingThe layers on the roof are repeated for the same purpose for other areas of the house. They work the same way. Some are installed the same way, some are installed differently. Other areas of your home have a different experience with water.

Tyvek TopThe outer layer of a wall, the siding, like the shingles, are lapped. The next layer behind the lapped siding is usually known as house wrap. That’s the white covering you see on many new homes, before the siding is installed. Technically, the term for this is ‘Weather Resistant Barrier’ or WRB. Just as the roofing felt helps keep water outside on the roof, the WRB helps keep water outside on walls.

Just as the roofing felt, shingles, and siding are lapped; house wrap should also be lapped, each new layer draining onto the top of the layer below. The directions call for a 6 inch lap, and then tape. The tape is used on house wrap and not roofing felt, because it is a different material, cap nails should be used.

IMG_7672How does the home buyer know the house wrap is right? It passed a code inspection, didn’t it?  This image shows damaged house wrap. Is it taped and lapped correctly? Are the fasteners used according to the manufacturer’s directions.

Do these problems mean that house wrap is bad.  Certainly not!  House wrap is a great product when installed correctly.  It will do the job it is designed to do; act as a Weather Resistant Barrier. It will then, direct water back outside and not allow it into the wall.

DetailWindows and doors need an opening in the wall. These openings must be detailed correctly or water will enter. These details involve flashings, and tapes. How the window is made, with nailing flanges, with foldable nailing flanges or field installed nailing flanges must be considered. Here we see a tape used to seal the nailing flange to the house wrap.

Is house wrap the only type of WRB used?  No!  It is the most widely used in this area. The others will be covered in a future post.

Now if the roof and the wall properly shed water, and they guide any water that gets inside back out, we get to the ground. At this point the water should be directed away from the house.  Gutters and down spouts do a great job when the ground slopes away. Recommended slopes are 1/4 inch per foot for hard surfaces like concrete, and 1/2 inch per foot for other surfaces. Local codes may require more, or a builder preference may result in a larger grade.

damp_proofingThe basement or foundation walls should be damp-proofed on the outside. This is the black spray applied to the concrete. A tile drain system is installed around the exterior of the foundation and tied into a sump to be pumped out of the home.

 

If these or other equivalent measures are built into a new home, the builder is doing the job right. They are all in the building code. The issue is not what material, the issue is quality of workmanship.

This post is part of a series of posts on A Healthy Home.