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5 Answers

Is there any way around putting a heat source in every bedroom?

I was speaking with an HVAC guy in my area today who reminded me that code says we have to have a heat source in every bedroom. We're planning on putting a single head ductless minisplit in our 1450 sf high performance home (to be built next year). Are there other exceptions/solutions out there, or do I just stick a Cadet heater in every bedroom and disconnect them after the inspector checks it off his list?

Asked By Alyssa Hoyt | Feb 4 16
2 Answers

Vapor Permeance of thick foam sheathing and board seams

I have read that at a certain thickness, all foam boards (eps, xps, and polyiso) lose their vapor permeance, effectively rendering them vapor retarders with very low perm ratings. Does anyone have a link to the research behind these findings and if so can I be pointed in the right direction?

I am hopeful that the effective thickness at which this condition occurs for each foam is stated on the research but I will hold further questions till I have read up on it.

Asked By Sash057 | Jun 18 18
8 Answers

Plumbing too close to edge of slab

A plumber set a vent pipe within a 1/4" of the edge of the slab on one of our jobs. When we told him to move it, he cried. I was surprised to find that this was not covered in our specification and I could not find it in code documentation. In fact, I could not find it anywhere. We have all seen concrete on the edge of a slab bust out around a vent stack or a piece of rebar that was too close to the edge of the slab.

So what is too close?

Asked By Hugh Stearns | Jun 18 18
2 Answers

HVAC duct size versus grille size

For proper air being returned to the HVAC unit that is the size of the duct have to correlate to the size of the grille for the return air? So for a 12 inch air filter grille what is the largest size return duct that could be attached to that for proper operation?

I’m getting air pressure coming from the attic through the switches ,outlets ,and around the drop ladder in a different zone than the one with what I believe is undersized return.

Thanks Rich

Asked By Richt1022 | Jun 18 18
6 Answers

Exterior vs Interior blinds

I know exterior has superior performance, but can anyone quantify how much? The latest heat wave has me lamenting the fact I didn't go with motorized, exterior blinds for the four east/west windows. Original plan was interior blinds. It's not too late to change plans, though the timeline is getting pretty tight.

Can anyone recommend a place to get these at a reasonable price? I priced them out locally last year, and they were a lot (I think four of them came close to the cost of a ductless minisplit).

Asked By Trevor Lambert | Jun 18 18
6 Answers

Ceiling insulation for a room addition to my house

I'm planning a room addition, 16 x 16 with a 6/12 gable roof and cathedral ceiling, zone 6. I'm not yet committed to anything specific so would like to run this scenario by folks for advice and opinion. I'm wanting to avoid the 5-6 inches of exterior foam (R-25) that would be needed if I went that route. And, I would like to go unvented. Would the following scenario work?

Asked By Howard Gentler | Jun 16 18
4 Answers

Building code requirements for stacked window headers, bracing, and stucco over foam

We are building in climate zone 5 and the county currently enforces the 2009 IBC & IRC.

We prepared a list of questions for our building inspector, some of which are location specific, but since we have gotten no response we figured some of this is probably common knowledge.

1. Do non-load bearing walls require structural headers?
2. Can vertically stacked windows of the same width share a header and king studs?

Asked By Zane Bridgers | Jun 17 18
10 Answers

Do I need an HRV/ERV for a house built in 1947?

I have a three-bedroom house, one bathroom, in Worcester, Massachusetts. It was built in 1947, and measures 1,100 s.f.

After purchasing it, I decided to upgrade the insulation in the walls and in the attic and air seal the home, and install new windows. All which was done through the Mass Save program. After completing, all the energy bills went down.

But the problem now is the house has high humidity and seems to be too tight and cause hard breathing. I have noticed mold that I did not have before. Also get headaches more often than I used to.

Asked By Will82 | Jun 14 18
40 Answers

Brick house insulation

All,
First of all, I wanted to wish everyone Happy and Prosperous New Year!
I would like to ask for an advice regarding a wall cavity composition. I am in Westchester County, 30 miles north of New York City, climate zone 4. I am about to acquire a brick house (tiny brick, maybe 2-3 inches thick). Single wythe, I believe. I think that brick is just decorative and is not load bearing at all. Only cinder blocks in the basement support the floor joists. Second floor ceiling joists are supported by wood framing.

Asked By Sebastian Smith | Dec 29 17
4 Answers

Circulating air between floors

I don't see a lot of air mixing between floors in my (partly finished) house. We had a hot day here yesterday (34C / 93F), and by sunset the first floor was 22C / 72F while the upstairs was around 24.5C / 76F. This doesn't surprise me, as hot air obviously rises, plus the 1st floor has the benefit of the slab heat sink. What surprised me is that this morning the temperatures were the same. I would have thought with minimal heating going on during the night, they would have equalized at least somewhat.

Asked By Trevor Lambert | Jun 18 18
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