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12 Answers

Metal siding — window head flashing detail

OK this keeps resurfacing so I thought I would see what others have come up with. When using metal siding (corrugated or sim.) dealing with the window head always seems to be a bit of a conundrum.Typically I see a piece of "J" flash utilized. But this usually points up, which may conceal the cut of the cladding panel, but consequently also catches water. Seems wrong. I have been trying to come up with an alternative and drew the attached, but surely someone more intelligent than I must have devised a better solution for this issue ?

Asked By Erik Lobeck | Mar 21 17
3 Answers

FPSF: Wing insulation with sub-slab insulation


For a frost protected shallow foundation, I was wondering whether folks who use sub-slab insulation also like to include wing insulation? Code doesn't require both.

I would expect that the wing insulation raises the temperature of the soil under the edge of the slab toward the deep soil temperature. This ought to have an impact on energy loss through the bottom of the slab, but is it significant?

Are there any studies that show the thermal gradient under an insulated slab, and how it's affected by the addition of wing insulation?


Asked By John Ranson | Mar 23 17
8 Answers

Material for preventing thermal bridging at steel beams and columns?

I have seen drawings showing an insert at the base of steel columns and where a steel beam bears on the top an exterior concrete stem wall (or in a beam pocket) that is intended to reduce thermal bridging at those points.

Does anyone know where to get this sort of material? A local structural engineer mentioned a carbon-fiber product that is quite expensive. He didn't think it would be worth the bother and expense. Anchor bolts (2 to 4) at each point will bypass the thermal break material.

Asked By Pat Kiernan | Mar 17 17
3 Answers

Need Roxul cover be entire to act as a rain screen?

In Zone 4, (Lawrence Kansas) we are rebuilding an 1883 house. For reasons of cost we have chosen not to take off the exterior clapboard, instead we are fitting 1.5" of high density Roxul between the studs and against the back side of the sheathing to provide a rainscreen. On top of this we will spray a thin layer of high density foam before blowing in another layer of dense pack cellulose to slightly built out studs.

Asked By Sacie Lambertson | Mar 23 17
1 Answer

Insulation of mobile home

We are renovating a 1976 single wide trailer. We have removed all the interior wall and ceiling panels. Currently the walls have the pre-existing pink fiberglass insulation and the aluminum siding, on the ceiling there is the same insulation and then plastic sheeting. We would like to add additional insulation before we drywall. We have looked into double bubble foil insulation, but then read an article on here as to why that would not be advised. What is the best product to provide more insulation that would resist mold/moisture from developing?

Asked By rich78 | Mar 23 17
5 Answers

How to detect a roof leak after having the underside of the roof deck sprayed with closed-cell foam?

I live in Buffalo, NY, and am renovating a Cape Cod style home. The interior is completely gutted and had a roof tear off and GAF system installed with no ventilation, with the plans for having the deck sprayed with closed cell. I had a question that no one up here can answer...

As the roof fails or if there is some sort of damage, how will I know if the underside is 100% sealed? My fear is the water will rot the rood substructure and hold mold. Is there any way to create a path for any potential leaks to follow??

Asked By cheezlo | Mar 22 17
3 Answers

Exterior foam and Roxul batt on a reno

Have a client who has an older house he just purchased . Scarsdale NY . He intends to put 1" rigid foam outboard of the sheathing with Tyvek behind and 1x strapping to attach siding .

Interior first floor walls are 2 x 6 , second and third floor are 2 x 4 . Question 1 is what R value Roxul should he use in the 2 different wall assemblies ?

Second question is , is Tyvek the right product to use as the only barrier between the sheathing and exterior ?

Asked By Richard McGrath | Mar 22 17
2 Answers

SIGA Majcoat vs VaproShield SlopeShield

I'm designing my LAST house-- my retirement home, after having built several homes over my lifetime. My last was in Vermont in 2000, using ICF, in-floor radiant heat (walkout basement with concrete slab, upper floor with 1.5-inch poured gypcrete), standing seam roofing, closed-cell spray foam under roof deck.

Asked By Peter Martin | Mar 23 17
14 Answers

How to make our walls and HVAC system more efficient?


Asked By Matthew Hicks | Mar 19 17
11 Answers

Do magic boxes distribute loads for ductless units?

For my pretty good home I am building( 2150 sq.ft. Zone 5 northern ct. near Sturbridge mass) I have recently got a quote back for mini splits. 5 heads 2 outdoor units Mitzi. Hyper heat. The contractor is at 17k installed. Diamond dealer. He has one head in each bedroom and 2 on the open floor plan. I am curious if there is a way to quantify how much a ducted ventilation system mixes the air around the home? Would a Minotair or cerv balance out the heating and cooling requiring more like 2 or 3 heads?

Asked By Scott Mangold | Mar 20 17
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