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11 Answers

Cracking slab

I had a basement slab poured in May, and it recently cracked in several locations. I am upset that the cracking did not follow control joints. The slab is about 5" thick, and I was aggravated to find that the control joints are only 1/2" deep. From everything I can find, 25% of slab depth is standard. Do I have a leg to stand on in asking the contractor to recut joints to appropriate depth and repair cracks? Slab is 4k psi with rebar on 2' centers poured over poly, 2" XPS, and ~9" crushed stone, in case it is relevant. Thanks for any input.

Asked By Jim Tyler | Feb 20 17
2 Answers

Filling a sunken floor and laying Tile.

! have a sunken living room floor and intend to raise it to the level of adjoining rooms. The floor has porcelain tile on it, is not cracked and has been in place 10 years. The present depth is 4 3/4" below adjoining rooms. The present plan is to raise the floor with 2x4's, plywood, hardboard or equivalent and use porcelain tile to finish it off. Is it feasible to leave the existing tile and build up over it?

Asked By Sammie Hodges | Feb 20 17
10 Answers

Metal standing-seam hot roof

Hi I'm building a new home for our family and wanted to run our roof design by you as my concern is moisture/ condensation. Essentially we have 2x12 members on a low-sloped 2 5/8" over 12 large 3500 square foot roof. I'm planning on insulating with 7" of closed cell (More if recommended) and no vapor barrier because of closed cell not needing it. The roof deck will be covered with Ice and Water HT and then have a standing seam metal roof installed on top of the ice and water. We are located in Massachusetts. One debate is do i use CDX , OSB Standard or advantech.

Asked By Michael Carreiro | Feb 12 17
4 Answers

Insulation recomendations?

Hi our new house is being built with 2x6 walls with exterior CDX plywood with Enviro Dri on the exterior. I'm debating open cell in the wall cavities vs dense pack cellulose. Any recommendations on either for both comfort and long term pay back. Is there any other options i should consider? Thanks for your help

Asked By Michael Carreiro | Feb 13 17
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
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