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6 Answers

Insulating a pier foundation floor in a marine climate

What's the best practice floor insulation assembly for a structure built on a very low pier foundation in a cold and wet marine climate?

I'm rebuilding a very small, very poorly-built, addition in south coastal BC (Canada). The addition rotted out, in part due to poorly managed roof runoff.

The climate here is damp year-round, with 50%-100% humidity. Temperatures go much above 60 F for eight months of the year. Winter means nine feet of rain with temperatures in the 40s (F) while summer means a few weeks of temperatures in the upper 70s (F).

Asked By Joe Smith | Dec 4 14
3 Answers

Plywood in the framing exposed to the elements for ~5-6 weeks?

Our new construction is in Pittsburgh, PA, mixed humid climate, quite rainy. We also usually have sleet and some snow in winters. The framing is to start 12/8/14. Windows and EIFS systems won't be installed until about mid-January or possibly later. Do we need to wrap the house in the Tyvek for the period before EIFS system can be applied? We thought of pre-treating plywood with liquid-applied weather barrier used in EIFS, but that can only happen at 40F and above and we won't have scaffolding/tenting until mid-January. The estimated cost for Tyvek is $800.

Asked By Lucyna de Barbaro | Dec 6 14
1 Answer

Flash-and-fill hybrid plus external insulation?

I designed a 2x6 dense-packed cellulose wall, fully sheathed in plywood, plus 3" of external Roxul Cavity Board. Climate Zone 6.

I'm trying to consider alternative wall types due to the added labor costs of external insulation, specifically the complications with fastening and window detailing when getting upwards of 3".

I'm trying to wrap my head around the Flash and Fill system described by Building Science Corp.

Asked By Meri Lewis | Dec 6 14
18 Answers

Exhausted By a House That Saves Energy


An article in the New York Times about a couple who built a very large net-zero house in Vermont, and are now regretting building too large and too complicated.

Asked By Jack Woolfe | Dec 4 14
4 Answers

I need help on building some DIY solar projects (portable)

I have done a lot of research and visited many sites but still cannot figure out a few things with a portable solar charging project that I'm working on... I need help with figuring out a solar design to charge say my phone. Is it possible to hookup a wall charger to the output part and it wiil do all the work? Also I'm including batteries and Need to know how to set it up so that the phone will be powered by the panels and battery and the charge will be there only when I plug in the phone... No wasted energy.
So here's all of my knowledge from research:

Asked By Shaye Miller | Dec 5 14
27 Answers

Options for garage heat

I would like opinions regarding options for heating a garage. I know, I know, "Why the H@!! are you heating a garage?" will come to mind for many of you. Others will agree that it saves on car repair costs, improves longevity, and allows for storage of "perishables" such as paint cans, bulk canned garden vegetables, and other things wife understandably does not want in house.

Here are the pertinent factors shaping the decision:
* Super-insulated house, Manual J heat load calc gives 12,400 BTU/h (3.6 kW) peak heating requirement (for garage alone)

Asked By Kent Jeffery | Nov 20 14
3 Answers

Rigid foam crawlspace insulation — vapor permeance?

We currently have an 18x30 crawlspace that is vented with batt insulation in the floor joists. The crawlspace also connects to a full basement that is 22x30. There is a 2'x2' opening between the crawlspace and the basement that is blocked with plywood, plus a few openings for ductwork and such. There is a radon mitigation system installed on the crawlspace floor, plastic covering that goes up about 10" on the crawlspace walls. HVAC supply and returns, plus plumbing all goes through the crawlspace to that section of the house.

Asked By HD S | Dec 4 14
1 Answer

Before people understood the need for a rainscreen gap

These days, conscientious builders usually install siding over a vented rainscreen gap. But back in the old days, however, wood siding was usually nailed directly to the sheathing, with only a layer of asphalt felt or housewrap between the siding and the sheathing.

When siding was installed without a rainscreen gap, the siding took a long time to dry after every rainstorm, and paint didn't last very long.

Asked By Martin Holladay | Dec 5 14
3 Answers

Air leak under new glass sliders

We just had new glass sliding doors installed a few months ago (there used to be a very old swinging door in that location, so the hole was enlarged and a new header was put in).

Now, I can feel a lot of cold air leaking in from the bottom. There is no moulding between the laminate floor and the door yet - I am in the process of putting quarter round moulding there, but there is a kick-lock so its taking me a long time to get the cut-outs right to fit around the kick lock.

Asked By Matt Solow | Dec 4 14
1 Answer

Should I fill the unvented soffits with foam?

We have an outbuilding that's about 12 x 13 that we want to turn into year round writing / guest room.
It has a basement where well equipment is located. We've sealed and insulated the ceiling and the floor joist bays above the foundation and covered with 5/8ths wallboard. With a tiny heater that comes on intermittently in the cold weather, the basement stays about 42deg F so the pump doesn't freeze.
We plan to improve the ventilation for the warm months when some condensation occurs.

Asked By Rob Cramer | Dec 4 14
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