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11 Answers

Could you moderate first posts to stop the flood of spam?

Recently, I haven't been reading the Q&A on GBA, because it's always full of spam. Could I suggest that you moderate the first several posts by any non GBA Pro user who hasn't posted before? The idea being that you either have to pay for a subscription or post three moderated and approved posts before you get unfettered access to the forums.

Asked By John Ranson | Jan 19 17
7 Answers

Thermal breaks for window bucks in double stud walls

We'll be buliding double stud walls for a new house, with the inner wall being structural (the outer wall will consist of modified Larsen trusses). Total wall thickness will be around 16" and windows will be "in-betweenies". This will be my first double-stud wall house and I'm working in the wall details trying to minimze thermal bridging.

Asked By Chris Chenier | Jan 18 17
0 Answers

Does anyone have a Mitsubishi Ductless Mini-split commissioning procedure?

Is anyone very familiar with the commissioning process of a Mitsubishi Ductless Mini-split. I am a stones throw away from zone 6 and had a Mitsubishi diamond contractor install what was supposed to be a hyper heating condenser unit. Instead the contractor installed the MXZ-3C30NA2 which is a non hyper heat unit. We had a couple days that we were down just below zero F and it seamed the unit was just maintaining. On the coldest day we had the remote thermostat set at 69F and the unit only was maintaining 66F. I have a well insulated 2100Sq ft.

Asked By Dillon Vautrin | Jan 21 17
10 Answers

Exterior wall polyiso worth it?

I live in central Texas and I'm debating whether adding 3/4" Polyiso to the outside of my exterior walls. would be worth the cost. I originally planned on it, but since my wife and I are doing the majority of the work, it has come down to just not having the time (we both work full time jobs, plus a bit more), and the initial cost of it.

Asked By Jacob Cox | Jan 17 17
9 Answers

ZIP Window Detail with Exterior Insulation

On ZIP's website, they have window details which appear to combine the flashing/window buck of an outie window, but it is shown flashing into a WRB (in this case the ZIP sheathing) located behind the exterior insulation.

Asked By Derrick Krienert | Jan 15 17
13 Answers

Mount outdoor unit on the wall or on the ground?

I am close to installing 3 fujitsu mini split units at our home under construction. Two outdoor units will be installed near each other, with the third installed in a different area of the house. The HVAC installer asked if I wanted to mount them on the wall or on the ground. I can't decide which I would prefer. Any thoughts on the pros and cons of each?

I live in central KY, zone 4A. We don't get much deep snow around here, maybe once every 10-20 years.

Asked By Clay Whitenack | Jan 18 17
6 Answers

Product for permeable lawn/grass instead of concrete paving

Seeking your advice on which is the best among that permeable products that allow you to have a lawn in an area that receives residential vehicular traffic and would normally be paved with concrete.

Asked By c l | Jan 20 17
4 Answers

Options to rectify attic system

I'm in a 1930's 2 story Colonial in zone 5 (greater Boston area). I have a furnace in my unconditioned attic, along with all of the ducting, which is leaky and has very little insulation. The attic floor is also filled with insulation gaps and air leaks. This appears to be absolutely awful for ice dam formation, so I'm trying to rectify the situation. I'd like to be energy efficient, but I'm worried much more about the risk of major damage from the warm roof in winter. I've put a thermometer up there, and when the furnace kicks in, it gets close to 60F when it's ~25F outside.

Asked By Mike S | Jan 20 17
1 Answer

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
8 Answers

Does anyone know if there is a manufacturer that makes an energy efficient, dual HVAC/ ventilation system that would satisfy both of my needs and eliminate the need for 2 duct systems?

I'm planning a moderate size home in SoCal in a semi-desert climate with adequate thermal mass. The home will have a tight envelope and my understanding is that some sort of ventilation system with separate duct work is required.

I was planning on an air-source heat pump to meet heating and cooling needs, but this will only be used in the summer and winter months mostly.

Asked By Paul Minotto | Jan 20 17
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