Monthly Archives: August 2014

A Healthy Home Part 2: The Home Starts Out Clean

This should be a no brainer!  Have you ever walked into a brand new home and found it dirty?  I haven’t.  The larger issue is really two things:

  • What gets designed into the home to assist the homeowner to keep it clean?
  • What goes on in the home before the cleaning service arrives?

Is there a small dirt factory installed in each new home when the builder isn’t looking?  No?  Well how does all that dust and dirt get in there?  If there is no conspiracy among the cleaning products industry to put dirt factories in our homes, then the dust and dirt must come from outside.  If that is the case,  a clean home should attempt to stop the dust and dirt at the door!

Mat A sidewalk, driveway  or patio should be included to enter the home. This can be swept or hosed off from time to time. It also provides a place for you to put your Welcome Mat!  Having one by each door is optimal in keeping your interior clean. Everyone in the family should learn to leave the gritty stuff in the mat.  It also needs to be cleaned regularly.

The designer should provide some type of entry area for people to remove and store coats, out door type shoes or boots, like a mudroom, hooks, baskets, or entry closet. Some type of seating for smaller, and experienced people, would be a nice touch.

laminateInterior design should utilize easy to clean materials. Floors, window treatments, wall finishes that are easier to clean will get cleaned more. The current trend with hard surfaces, like laminate and hardwood, are perfect examples of cleanable materials.  The move from the shag type carpet to the berbers and other short napped carpets is also great for being easier to clean.

The use of semi-gloss latex paints instead of flat or matte finishes is helpful, because such surfaces are easier to clean using mild soaps. I know some interior designers will want to use the flat or matte types. Those should be limited to places that small peoples fingers do not try to decorate. If flat paint finishes are inevitable; wiping the areas down with a set sponge instead of a rag will help keep the finish intact.

Hole In WallThe other place to keep dust outside are the holes in the house.  Windows, places pipes, wires, and other parts need to go from inside to outside.  These should be sealed.  Most builders do a great job on these places in the walls.

Instead of covering the outside of the framing with 1×8 boards, as my home was, they use 4×8 sheet goods today. These provide structural strength and cut down on the holes for dust to get in. The use of house wrap type coverings also helps with dust control.

Infrared Image Infiltration in Knee WallThe remaining area is the attic.  This is a challenge for most builders. Some of it can be done before the drywall is up. That part is fairly easy.  Some of it must be done after the drywall is in place.  Attics are not exactly a great place to work. The work must still be done. The Infrared image on the right show air leaking into a home from unsealed attic joints. Yes, it is a cooling problem in the summer, it is also an opening for dust to enter the home.

1 Inch drillGap Not SealedHoles in the attic don’t have to be small.  The picture on the left shows one type of hole. These can be filled before the drywall is hung. They are some of the easier holes.  Electrical, plumbing and others need these holes. They also need to be sealed.  A little caulk or foam in a can does the trick. Other holes are smaller, and this picture shows them also.  Look carefully at the 2×4. On each side of the wall is drywall, (the white stripe) This needs to be sealed also. These holes occur on both interior and exterior walls. Both types of walls need to be sealed. Where do the wires go, light switches and plug outlets.  You have seen the foam gaskets sold at the home supply sections for these.  Sealing at this point is better, and in new construction is easier. The image on the right above, is a better image of drywall gaps. There are clearly two.  The first I saw from the attic side, because light from the room below was coming through. These were the small holes you see on top of the edge of the drywall. The flash on the camera makes them show as dark spots. The larger gap between the drywall and the top plate must be sealed also. Drywall Air leak

The thermal image above shows both types of leaks. It was taken during a blower door test from inside the home. The picture in the attic, above right, was the other side of this vaulted ceiling.  On the right side of the wall ceiling joint the air leakage is very defined, these are the small holes noted above. Climbing a ladder with the blower door running, allows you to feel the air movement.

The left side of the image shows the effect of the gap on the back side. The air movement fills the whole wall cavity and degrades the performance of any insulation present. This wall separates the garage from the house and was insulated. Because the attic was not properly air sealed at construction, the infiltration from air leakage, was causing the walls to leak heat as if they were not insulated at all.

The way to verify these holes, the big ones, and the small ones, are not left, is a Blower Door Test.   One of the last steps in finishing any house should be a blower door test.  The builder can use these results to verify the quality of workmanship from all subcontractors on the site. The homeowner can rest assured the builder testing all homes with a Blower Door is not getting a house with big holes. And the house doesn’t have very many little ones either.

A Blower Door Test is part of a HERS Rating on the house. The current cost of a new home in the hundreds of thousands of dollars, the cost of a blower door to the builder is rather minor, compared to the peace of mind that results from a job well done.

A short Blower Door Video on You Tube. This will open in another tab. It is less than 3 minutes.

This post on one in a series on Healthy Homes.

 

 

A Healthy House Part 1c: How Dry is Dry

rainIn Part 1a, we have looked at how your builder builds your home to keep water from the outside from damaging your home.  He used materials to shed the water and he lapped them over each other, from the roof peak and the shingles all the way down to the ground. And then directed the water away from the house, using gutters and sloping the landscape away from the house. Easy, quick and it looks nice.

In Part 1b, we looked at how your builder builds your home on the inside to keep water where you want it, and provide easy clean up when it does get out of the pipes, the sink, tub or shower.

BucketYou can think of this as bulk water.  You can see it, this is water that is usually measured in quarts or gallons, and it is responsible for 50 – 60 % of the water damage that occurs over time. The exact percentage depends on the source doing the figuring.  So why is there a Part 1c?   There is one remaining source of moisture in most homes.  Water Vapor.  Hard to see it, hard to measure it.  The damage water vapor causes is usually found to be very extensive.

If you have a roof leak, it usually ends up inside and you find it while it is relatively small. When it is fixed the damage is limited and fairly easy to fix.  Leaks from plumbing and over flowing sinks and tubs, is usually caught very fast. The surface is easy to clean up and many times contains the water.  Damage from these sources doesn’t really occur unless the water continues over time to get there.  It stays wet and is not allowed to dry out.

Flood type events are not really of concern here. When they happen, the homeowner is aware, his insurance may cover repairs and there are lots of contractors that will do the work. Generally, they have little to do with how the house was built.

teapotWater vapor is present in varying amounts in every home.  What is the relative humidity in the home?  40% – 25% – 65%?  That is water vapor in the air. We add to that from breathing, cooking, and hygiene activities, like showers and running hot water for various purposes.

How do we control this water vapor?

Spot ventilation.  This may be as simple as opening a window next to the stove where the pasta is boiling, or the tea pot is ready to pour. It may be using an exhaust fan over the stove to actually remove the water vapor from cooking out of the house. Same in the shower.

acWhen the heat and humidity arrive around here, in the summer, it is air-conditioning season. Most air conditioners will lower the temperature of the air and remove some of the humidity at the same time.  Somedays they do a great job, somedays the ac unit really has to work and it.  Occasionally, you will find a unit that makes the room fairly cold, and you just feel clammy.  Like you just walked in from 100° outside and you are wet all over. The trouble is, it doesn’t go away.  You keep feeling cold and clammy.

That is the first way that water vapor causes a problem with our homes, it makes us uncomfortable.

How does the water vapor move into the walls and attic to cause problems like the liquid or bulk water we looked at?  It has two ways to move.  Air Movement and Vapor Diffusion.

Vapor Diffusion involves moving a vapor, in this case water.  It involves temperature and pressure.  It also involves Math, lots of fancy math.  I know some math teachers that can run these numbers, and a couple of physicists here in Kansas.  I’m sure the characters on TV’s ‘Big Bang Theory’ could run the numbers.

Adding MachineThe good news is, we don’t have to run the numbers.  If you take a room in your home with the humidity at 40% and 70° –  you will find less than a gallon of actual water.  By the time all the numbers are done, the answer is:  Yes – Vapor Diffusion put some of that water vapor into the wall.  And we can test that the 7% moisture content of the drywall, studs and other parts of the wall, is now 7.5 or 8%.  Not much change.   If you have read much on this blog, you know I lower my blood pressure by turning wood, into bowls.  Anything less than 12% moisture content in wood is considered dry.

If the builder bought kiln dried lumber, and kept the rain off it, while the house was built, the wood is probably 8 – 9 % moisture content when the home is finished.  Kiln dried lumber is typically 6 – 8 %.  Moving from an enclosed type shed to the job site, wood will pick up a little moisture.

What about air movement and water vapor?  That is the one to take care of.  Uncontrolled air movement takes the water vapor right along with it. When that vapor comes in contact with a surface that is below the current dew point, it will condense and the liquid wets the material.  We know that energy savings is easy to obtain with air sealing.  So fixing the air leaks is good for stopping the water vapor from making our house wet also.   How much?  This graphic from the guys at Building Science Corporation shows how much.

Air_Vapor

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

A Healthy House Part 1b: How Dry is Dry

In the first installment of A Healthy House, we looked at water issues.  Specifically, water from the outside of the home.  Most of this type of water is directly from what the weather refers to as ‘precipitation’, or rain and snow.  Even the ground water we looked at were related to rain and snow.  There are other types of water issues.

pipe_leakFirst would be a plumbing problem.   You can have a leak in a water pipe, or a sewer line.  I know, sewer lines generally do no leak, they slow down, or plug up and then back up.  Either way there is water in the house, and someone is cleaning it up.

Many plumbing leaks like this or sewer problems are an ongoing maintenance issue. Not much can be done during construction.

Situations like the drain line, getting stepped on and thus the floor drain is the highest spot in the floor is a construction issue.  It takes all the trades to help finish the building correctly. The plumber may have done it right, only to have someone else step on the line.

A nail accidentally driven next to a supply pipe, may cause a problem later. If you have copper, 2 dissimilar metals touching will eventually cause a leak.  A nail next to a plastic line that moves, can also create a leak. You may find great work in a home and good, conscientious, plumbers, drywall installers, electricians and others. Sometimes these defects are hidden, like the tip of the nail inside a wall. So maintenance becomes an ongoing effort.

daltile-Bath-Accessories01Thoughtful design can help.  Specifying hard surfaces for areas within a few feet of tubs, showers, toilets, sinks and laundry facilities is important. Most leaks, spills and accidents will occur in these areas. An easy to clean surface that doesn’t hold the moisture is essential.  Carpet has it’s place, just not near water. Some floor coverings such as linoleum or cork type flooring may also not be appropriate for these areas. (Image to the right is courtesy of DalTile.)

 

Hard SurfaceAppropriately located floor drains can help.  Use of appropriate materials in the floor structure is a good thing. Most homes in this area have a basement, meaning a wooden subfloor is under and of these facilities on the main or upper floors.  The proper type of sub floor in these areas is crucial to keeping the home dry. It is also helpful in drying, when the floor does get wet and not encouraging mold growth, as many types of common building materials.

This post is part of a series of posts 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.

 

 

 

A Healthy Home

Healthy HomeBuilding a new home, gives the homebuyer an opportunity to build in all the things they want. The floor plan, bedroom arrangement, windows are all important.

Also right up there is a house that is healthy. Everywhere you look, someone is pitching, this is healthy for you.  We have lots of buzz words for healthy.  Organic, whole grain, anti-oxidant, reduced fat, low sugar, wellness, all-natural are but a few. How do you make a house into a healthy home?  It starts with design and a few simple objectives.   Ideally, a healthy home is:

  • Dry
  • Clean
  • Well Ventilated
  • Combustion by-product free
  • Pest Free
  • Chemical Care
  • Comfortable
  • Safe

read beforeIt seems fairly simple.  We want a roof over our head to keep the elements out.  Hot or cold, rain or snow, we don’t want them in our home.  The dry home starts with a well constructed roof.  That keeps the weather related water like rain or snow out. Then the walls, and the foundation.

Clean may be obvious, or not. Well Ventilated and Combustion by-product free, along with pest free, no toxic chemicals, comfortable and safe seem also to be obvious.  There is a saying about the Devil being in the details.  It is certainly that way in building a home. So a few details on these topics that make up a Healthy Home are important.

I will be posting a series based on the Healthy Home. We will take a look at each of the points listed above and what they mean to the home owner.

Part Ia   How Dry is Dry       Bulk Water from Precipitation

Part 1b  How Dry is Dry       Bulk Water From other Sources

Part 1c  How Dry is Dry       Water Vapor

Part II    The Home Starts Out Clean

Part 3    Well Ventilated

Part 4     Free of Combustion Byproducts

Part 5     Pest Free

Part 6     Chemical Care

Using One HVAC System for Two Areas

My first audit was triggered by the homeowner concerned that the upstairs was several degrees warmer than downstairs. Since we all have experienced Hot Air  goes up, it makes some sense.  In this case the difference was 15° F at 8:00 am, rising to 20° F by noon that August morning.  Yes, it was hot.

4 square craftsmanThere are a number of ways to help this out, for existing homes. Which one is best depends on the specific home, the existing setup and the homeowner.  For new homes, it usually falls to the HVAC guys to work out.

In a new 2 story home, it is common to see two HVAC units.  One in the basement for most of the home and one in the attic for the second floor.  Some builders, concerned with cost, or space considerations, will try a Zoned System.  You can also find Zoned Systems in single story homes, with the master suite on one zone and the rest of the home on another zone.

furnace bypass zoneTypically, the set up uses a bypass and several dampers to control the air.  The wisdom of this approach is that changing the air flow through the unit costs a lot of $$$$.

In the video below, John Proctor, goes through the measurements and calculations of using or not using a bypass and dampers to figure out exactly what is happening.  His conclusion:  The Bypass Damper set up costs 22% – 32% more.

This video is primarily written for HVAC contractors and others interested in the details and workings of air conditioning.  If all the numbers make your eyes glaze over, that is OK.  All you want is comfort, a Bypass dampened system may do that at a cost. It may have the cost and not do that.  So if you are considering a Zoned HVAC system,  tell your contractor —  ‘No Bypass Dampers’!  And refer them to this post.