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13 Answers

Mortar bridging and droppings

General question on Mortar Bridging and Dropping workmanship.(CZ4)

Here are a few images of some brick veneer on a house. Its not mine, but it is from the builder I will be using. I've read that droppings and bridging are "bad" but I don't know what constitutes good vs typical vs poor. So I've attached some pictures to get others viewpoint on the quality of this work. There is a single layer of tyvek and then OSB behind that, and I'd say ~1" of space behind the veneer, at least where there is not bridging.

Asked By Stephen Cook | Jun 16 18
14 Answers

Dirty electric from minisplit ductless heat and air conditioning

I saw a u tube video on a Fujitsu mini split system air/heat...where a building biologist specialist was testing a persons house for dirty energy. He found from the box on the outside of the house had very high amount of electro magnetic interference... and determined that it came from a Fujitsu Mini Split system... he used filters to try to eliminate the energy...which worked for everything but the Fujitsu System. He said the spikes were the same type that causes occular melanoma cancer.

Asked By Arleendv | May 30 18
6 Answers

Bonus room temperature and humidity

We just moved (CZ4, humid) and have a finished bonus room above our unconditioned garage. The insulation is poor. Heat is electric baseboard. AC is currently none. The room is not in regular use. For example, we did not turn on the heat this winter.

If the room were in use, it would be ideal for a minisplit. But, we rarely use the space. Other than a large tub of DampRid, there is nothing up there to protect the space.

What do we need to do to avoid problems from seasonal temperature swings and/or humidity? Can we simply leave it closed and locked, excepting when we have houseguests?

Asked By FrankFulton | Jun 15 18
8 Answers

Room over garage


Climate zone 4c / Seattle / New construction

We are building a new house which has a studio over the garage deck. The raised subfloor of the studio is built with 2x4 sleepers over garage deck. The subfloor sheathing for the garage deck and studio is Advantech.

How do we detail the void spaces between the sleepers? I am worried about moisture getting in there either through condensation or leaks. Currently, the plan is to fill the voids with XPS and tape the seams. However, I don’t trust this solution to get rid of all air pockets.

Asked By Jay Raja | Jun 16 18
4 Answers

Load calculation questions

We have just hired a ResNet rater to complete room by room load calculations in our new home (CZ4, humid), prior to interviewing HVAC contractors.

The first load calculations are about 73k BTU peak heating for the whole house. Our goals are thus 1) confirm model inputs and 2) identify envelope upgrades to lower peak heating load to 60k, so we can pursue a 5 ton air source heat pump. We'd consider zoning but are not sure hoe much this would increase efficiency or comfort with ASHP.

We like and trust the rater, just confirming a few things with the experts here:

Asked By FrankFulton | Jun 15 18
4 Answers

Securing wall sheathing

I have two questions about securing plywood wall sheathing:

1) Many local contractors are now using staples to secure sheathing instead of nails. I never heard of that. I realize that it can meet local code, if properly installed, but will it do an adequate job of earthquake resistance in seismic zone C? (moderate risk) We also occasionally get high winds or tornadoes.

Asked By Debra | Jun 14 18
3 Answers

To caulk or not, above a 1925 redwood window head jamb?

I was just pulling out the caulk gun, when I noticed this head jamb is tapered.

The house is 1925 stucco in USDA zone 10b (San Francisco Bay Area). So did the original builders intend this as a form of weep? Instead of caulk is it actually better to leave the edge open, or cut a weep into the caulk?

The stucco wall in question is settling, and has various patched cracks. So, in theory at least, water may weep down the old tar paper behind the stucco, during the rainy season. The walls are at least partially filled with cellulose, which reduces drying to the interior lathe and plaster.

Asked By Bryce Nesbitt | Jun 11 18
9 Answers

Roxul ComfortBoard installation with siding

We are using 2x6 construction with zip system, 2" of roxul, furring strips and siding. My question is what to do with the extra 2.5" cavity that this will create at the bottom. Is the best practice to move the walls in, install a pest scree, etc? Thanks

Asked By User-7088022 | Jun 12 18
10 Answers

Heat pump recommendations (central system)

Hello Gents,
I have been lurking here, pretty much since I bought my first new home, (11 years ago) and realized how little I knew about this huge purchase.
It’s a 1650 sq. ft. two-story house, in Montreal, Quebec, (zone 5a) built in 2007. It has central heating, electric furnace with the original 2.5 ton heat pump, which has just let go.

Asked By Sean Herbert | Jun 11 18
9 Answers

Insulating top of basement slab - Is moisture still a problem with a barrier?

Is insulating the top of a non-walkout basement slab floor in climate zone 6 really valuable if the slab has a moisture/vapor barrier beneath it? Goal is carpet on top for most to the space. What happens in the event of water flooding from a toilet or clogged drain?

Asked By BobTheWeekendWarrior | May 4 18
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