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10 Answers

Is it OK to step the slab thickness over the footings to accommodate insulation between the slab and the footings?

I am building an addition on my home near Ottawa and I am adding two new sections of full-foundation on either side of the existing foundation, which has no under-slab insulation. I am adding 3 inches of insulation under the new slab, however for various reasons it is not practical to bring the 3 inches of insulation over top of the footings and right to the inside edge of the foundation wall.

Asked By Chris Seligy | Sep 2 15
5 Answers

Penetrations in exterior foam and rainscreen

I will be installing 3 or 4" of exterior foam with a 3/4" rainscreen and installing new windows and siding. This will be my first retrofit of this type.

Asked By Brian Otten | Sep 3 15
11 Answers

How can I properly vent my tiny house roof (it has cross member framing instead of rafters)?

I have the framing almost complete on my tiny house, but I have run into a stumbling block. Framing the roof with cross members instead of traditional rafters made a lot of sense because the shorter span allowed smaller lumber for more head space and less weight, but upon further research my plan for venting is not going to work (I know - proper planning prevents poor performance). See attached picture for framing structure.

Asked By Ryan Reed | Sep 2 15
4 Answers

New 20+ SEER Variable Carrier heat pump w/ Greenspeed Intelligence system creating moisture & performance problems in the crawl

I had to replace 2 -13 SEER HVAC split systems in my house about 2 years ago do to some Sandy storm damage. One split system was a 90% gas furnace with a 3 ton 13 SEER AC and the other was a 2 ton 13 SEER heat pump.

Asked By Bruce Howe | Sep 2 15
5 Answers

Building codes

I often see posters refer to building in areas with no codes. Here in Canada, although we have areas in which there are no permits or inspections, the building codes are enacted to cover the whole of each province or territory. People building in areas where the codes are not enforced have the same obligations to follow them as elsewhere.
Are there areas in the US where there are no codes and you are free to build as you like?

Asked By Malcolm Taylor | Sep 2 15
1 Answer

Can construction foot traffic on the roof dislodge or break the seal between the foam and the sheathing?

I am having the underside of my roof (flat roof-1/4"/12) sheathing sprayed with 2" of closed cell foam (flash/batt). I am concerned that construction foot traffic on the roof will dislodge or break the seal between the foam and the sheathing. There is quite a bit of flex in the roof sheathing. Is my concern valid?

Asked By keith messick | Sep 3 15
14 Answers

Why is there condensation on the return ducts and mold in the attic as well 60% humidity throughout the home?

This home has since been remodeled, including all new metal duct work and insulation. The issue that we need to resolve is the high humidity in the house at about 60-65% even though the unit is running efficiently. There is quite a bit of condensation on the return ducts in the attic as well. We have had two reputable Heating and Cooling Contractors come to assess the situation to no avail. The owner attempted to contact the original Mechanical contractor, but has not been able to speak to anyone yet.

Asked By Jimmy Miller | Sep 1 15
4 Answers

Roof ventilation ideas

I'm trying to add attic ventilation for my whole house fan, as the manufacturer states that I need a total of 4.4 sq. ft. of free air. I currently have gable vents, but they're located right above a window and the attic air gets sucked right back into the house (even when the window is closed, to some degree, and I'd like to open that window anyway). So I'm thinking of sealing off the gable vents and getting all the ventilation from the roof.

Asked By Robert Shelton | Aug 26 15
7 Answers

Any hydronic system controls with low standby electricity consumption?

I was feeling good about the changes I'm making to reduce the electricity consumption of my hydronic system: a Grundfos Alpha ECM pump that is consuming only 16 W when it's running, and Taco "sentry" zone valves that use about a watt when on. But I measured the power consumption of controls last night, and it can add up to almost as much as the pump: 3 W for an aquastat, 6 W for a Taco "switching relay" circulator control with one zone on, and 4 W of standby power for the 40 VA 120:24 VAC transformer that powers the zone valves.

Asked By Charlie Sullivan | Sep 2 15
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