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21 Answers

Insulation retrofit

Looking for some advice on a smallish rehab project I am about to start. I've read many of the great articles and Q&A discussions here, so I think have bit of direction...but as I am novice, I am interested in some feedback before I moved forward.

In GBA Pro help | Asked By Jeremy Kachejian | Jan 12 17
5 Answers

Trying to understand humidity dynamics.

The gym I go to leaves a large box fan on in the locker room 24 hours, presumably so the air movement will dry surfaces (wet floors). I can't imagine they would think it would help with wet clothing left inside the lockers. Accepting that this is inefficient, is it efficacious?

I also know of an archives building that keeps fans on low all the time, with the intent to keep historic articles—especially ones with fabric—from getting mildew. There is a dehumidifier in the room also that keeps humidity below 60%.

In Energy efficiency and durability | Asked By David McNeely | Aug 12 17
2 Answers

Insulation on a 2/12 pitch

Hi all I do love this site it has so much information on it
I am in the planning stages of a new home hope my last stop before I leave earth
I is a mono pitch it will span 32 ft at its widest part I will be using 24in parallel trusses we are in lower michigan north of Detroit.
My thinking is 18in of fiberglass it will leave me with 6 in of air on top and a vent running all the way along the soffit and Ridge
Will this work?
I was thinking if I do need more air in the middle I can put a small step in the roof to grab more like 2 in or so.

In Green building techniques | Asked By Robertsoave | Aug 18 17
6 Answers

Ridge vents: are they susceptible to snow drifts and driving rain?

My current design incorporates ridge vents with simple gable roofs (both house and garage).

It seemed to be both the aesthetic and performance choice. I will be using standing seam steel roofing, which seems to have a very water tight ridge vent design.

In GBA Pro help | Asked By Mai Tai | Aug 17 17
4 Answers

Low-slope roof

I am building a PGH and I have a 32' run of unvented, low-slope roof that we will start framing out shortly. The interior stack-up is gypsum, 2x3 service cavity, Siga Majrex air and vapor control layer (let's vapor out of the cavity, but not in), 2x12 joists, dense pack cellulose between joists, 3/4" Advantech seams taped with Wigluv. I was planning on using a unvented nailbase product that has 4.5" of polyiso with a layer 1/2" osb attached to the top. I am in Zone 4 and this will provide more than the required .31% of exterior to total r-value even if I de-rate the polyiso r-value to 5.

In Energy efficiency and durability | Asked By Jonathan Lawrence CZ 4A New Jersey | Aug 18 17
28 Answers

What heating system should I install in my 150-year-old house in Connecticut? Oil boiler, ductless minisplit, or something else?

My family lives in a 2-story 2000-sq.ft. balloon-framed house in Western Connecticut (zone 5A). We currently heat exclusively with a Harman XXV pellet stove, which surprisingly keeps most of our house pretty comfortable even in the depths of our cold New England winters. Of course there are some rooms that will get down below 60 on the coldest of nights, but that just means we stay in the warm parts of the house, which works fine for us. We used to heat with a Burnham RS-111 oil-fired boiler piped through about a dozen beautiful and massive cast-iron radiators.

In Mechanicals | Asked By Rob Wotzak | Nov 9 14
1 Answer

Chimney chase insulation

I have read a lot of articles and forum posts about this, but there is not a lot of consensus, and each answer seems very case specific. So, here is my case! I am installing a RSF Focus 320 [Editor's note: This is a manufactured fireplace with a glass door; the fireplace is designed to burn wood.] in a new construction home in NC with outside combustion air and a hookup to our HVAC system for distributing heat.

In Energy efficiency and durability | Asked By Kevin Spellman | Aug 18 17
4 Answers

Foam over Platon dimple mat on foundation

We are stumped at a stage in our building process. Winter is here and we need to deal with our foundation. Our site is dry dry dry, but we are not ready to just attach foam to the cement and backfill without any effort to damp/water proof the foundation.

We are essentially forced to use a mechanical system as the weather and temperatures (-10 degrees celcius and wet) are making any other sort of damp/water proofing impossible (as far as we know).

In Green building techniques | Asked By jessie pratt | Dec 11 12
4 Answers

Best waterproofing to be used over ICF walls

Just put up the ICF walls and filled with concrete on our well insulated house in Zone 7. Was planning on using Grace Bituthene. It seemed to work well on another storage building constructed with the same ICF walls.

The area is properly drain tiled, and the house is in a fairly well drained area to boot.

Just wondering if there is maybe something better out there?



In Energy efficiency and durability | Asked By Steve Lenertz | Jun 29 17
7 Answers

Housewrap under outsulation foam

Can you tell me if the housewrap actually serves a purpose underneath foam board?

In Green building techniques | Asked By Joshua Terry | Aug 3 17
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