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4 Answers

Insulating diagonal hardwood sheathing in climate zone 3 - insulated lap siding + drainwrap?

My wife and I are completely renovating my great grandparents' house in central Mississippi, and we will soon replace the siding, much of which is in bad condition. As we have looked at options, the insulated Hardie lap siding has been one recommendation, with the idea being that Tyvek drain wrap would go between the back of the siding and the beautiful diagonal sheathing.

Asked By Joel Fyke | Feb 13 17
6 Answers

SIP roof with roofing sleepers

I want to create an air space between the SIP roof panels and the finished roof. I am taping the SIP roof seams with SIGA tape and installing a breathable roof membrane (Majcoat).

I want to create an air gap between the finished metal roof and the SIP. I was planing to use 2x's but the problem is which way to run the boards?

Asked By Peter L | Feb 10 17
2 Answers

Second story hydronic radiant floor system

We notice that the hydronic system for the 2nd story tends to warm the ceiling of the 1st floor rooms below rather than the floors as was intended. Our second story was built with hydronic loops between the floor trusses on the underside of the subfloor using thin metal (not aluminum) heat transfer plates. Laminate flooring and some tile in the bathroom cover the floors. I read and others suggested to blow insulation between the floors and insulate the ceiling cavity to force the heat upwards.

Asked By Greg J | Feb 10 17
3 Answers

Are there any knowledgeable pros available to help design and plan a balanced ventilation system with ERV for a residence?

I have been trying to find some help with a residential air exchange/ventilation system for our home for some time now, figured perhaps someone here on GBA might be able to steer me in the right direction, or at least help me figure out a few specs if I end up having to do this myself as a homeowner, without any background in construction or engineering whatsoever.

Asked By Natasha Reeves | Jan 29 17
7 Answers

Footing capillary break vs. bonding of masonry to footing

I am an architect in Ohio where we often use CMU for foundation wall, especially on addtions. I've been showing "damp proofing as capillary break over footing" on my wall sections based on GBA recommended details. I recently got a question from a mason about this. He had never heard of this detail, and was concerned that it would create a bond break, preventing the mortar from properly connecting the block to the footing. Is his concern a valid one?

Asked By Hallie Bowie | Jan 26 17
16 Answers

Non-typical installation of XPS and 8 ft. wall with 9 ft. ceilings

I am in the early stages of framing up a basement wall. Exterior of foundation is almost all exposed. I plan on 2" xps, backed by a 2x4 stud wall, then possibly filled with insulation.
I originally wanted to have the rim joist accessible for future leak detection and planned to incorporate a perimeter soffit for wiring/ and access. This would give a finished tray cieling for the basement. And still have 9ft in the center of the room.

Asked By Austin K | Jan 25 17
4 Answers

Best way to air seal and insulate floor and wall assemblies

I'm remodeling a house in climate zone 4 outside Seattle. The existing exterior walls are 2x4 with 1x8 board sheathing. I want to achieve the required R21 insulation value without having to fur our the wall to achieve a 51/2" wall cavity while also sealing the 1x8 sheathing. The subfloors are 2x6 T&G and I want to seal the floor assembly and achieve the minimum R30 insulation value. What would be the best strategy to achieve these goals?

Asked By Stewart Breslin | Jan 21 17
11 Answers

Insulation for vaulted ceiling

We re-roofed our house this summer and found a lot of damage over our family room with a vaulted ceiling. We replaced the plywood and are now redoing the underside. The roof has a roof ridge vent and ventilation holes in the soffits. We are creating on-site baffles with 1" rigid foam boards. We are planning to use R30C insulation which is denser for cathedral ceilings. The question is do we use faced or unfaced, and do we need to use plastic sheeting as a vapor barrier? We want to get it right this time!

Asked By Kim Howard | Nov 22 16
3 Answers

Smoke odor

Hi, We are restoring a severely fire damaged home and while many components have been simply removed (down to the studs), the framing needs to be treated to eliminate the smoke odor. Our research has pointed us toward alcohol based shellacs. Some say first use an oil based primer and then the shellac. Can you advise?
Thanks, jk

Asked By Joseph Klockner | Jan 23 17
1 Answer

How should moisture/vapor wetting and drying be considered in this situation?

- Climate Zone 6, Marine setting
- Stand alone garage(1970's) to be converted to an overflow guest house w/ full bath no kitchen.
- Guest house to be used in summer only.
- Existing structure on a floating slab w/ no vapor barrier beneath, sitting poorly drained soils.
- 20' by 16' area w/ cathedral ceilings, 2x4 walls and 2x8 rafters
- 20 mil vapor barrier to be installed over slab (seams taped), may not be able to extend under existing perimeter walls.
-2x4 sleepers laid flat over 20 mil VB
-1 1/2" xps fitted between sleepers

Asked By geoff summa | Jan 16 17
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