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2 Answers

Is Rmax Thermasheath-XP an acceptable alternative to Dow Thermax?

I intended on using Dow Thermax for an exposed basement application in a residential setting.

I thought there were no alternatives without using an ignition barrier (drywall) but recently came across Rmax Thermasheath-XP. For my purposes, I believe this would be a more affordable option.


Does anyone have any experience with this product? It seems to have similar properties to Dow Thermax. Does Dow Thermax have any documented advantages?


In Building Code Questions | Asked By NatePa | Apr 19 18
3 Answers

Roof/Ceiling R-Value Requirement

I'm trying to understand what level of insulation is required in my roof/ceiling based on the 2012 energy code for Zone 5. Based on the tables I've looked at, R-49 looks like the basic requirement, but I'm trying to figure out if I can step down to R-38 or even R-30 based on what I plan on doing? Here's a few of the details:
- I will have no attic (100% vaulted ceiling)
- There will be no cavity insulation between the rafters. All insulation will sit on the structural roof deck and be continuous.

In Building Code Questions | Asked By rodrob15 | Apr 19 18
6 Answers

Energy end-use monitoring system for both electricity and natural gas energy sources

I am looking for an energy end-use monitoring system that we can use in buildings that use both electrical and natural gas energy. There are a lot of really good electrical energy end-use monitoring systems, but very few that include the ability to connect to natural gas meters. The qualities I am looking for include:

- Reasonable capital cost that allow the system to be used by cash-conscience organizations (e.g. affordable housing) who are eager to reduce their energy costs

In General questions | Asked By Greg Leskien | Apr 16 18
1 Answer

Are solar panels today carbon footprint break-even during (and after) lifetime?

I know this is ever changing, and big effort is being made to find new ways to produce PV panels from cheaper/more environmentally friendly materials, but if I were to buy PV panels today, will they ever reach carbon footprint break-even point, when we take into account their production AND waste management?

On some soruces, I've found that getting rid of these panels is a big problem, because of the toxic materials used. How big a problem is this?

In Green products and materials | Asked By Davor Radman | Apr 19 18
1 Answer

Cedar ceiling in bathroom?

I want to install a cedar ceiling in my bathroom above the shower over the existing Sheetrock. Is there a vapor barrier needed or will i need any airspace between the ceder plank and the Sheetrock? I want planning on using any sealant on the wood. just tongue and groove planks and brad nail it up. Thanks for any help.

In Interior design | Asked By Cyprus2400 | Apr 18 18
7 Answers

Mold Remediation

Anyone have mold remediation on a commercial building experience or been/are in the mold remediation industry?

I have a maintenance contract on this building that just started, could smell a strong mildew odor in a unit on the top floor north side of the building when completing a PO. Was doing top floor work in the south side of the building no odor. Slight odor in hall at the midpoint of the building top floor. It was unseasonably warm that day, mid 40's high temp.

In General questions | Asked By T Carlson | Mar 5 18
11 Answers

Comfort Board 80 vs 110 - density worth extra cost?

For our upcoming house build using 4" of rigid mineral wool we have been quoted for both Roxul comfort board 80 and 110. Over the top of this we will install 2x4 furring and cedar siding.

The 110 has a compressive strength of 1120 PSF at 10% deflection, the 80 is only 439 PSF at 10%, using the 110 will simplify the installation of furring as it will compress less, but I don’t know that the furring installation sub would price their install any differently between the two products. (Furring install not by insulation contractor).

In Green products and materials | Asked By Chris Armstrong | Nov 16 16
2 Answers

Thermalbuck Insulated Window Bucks

A person on my thread about Roxul Comfortboard vs ZIP-R Sheathing suggested that I use this insulated window buck when using the Roxul system. I never knew this type of product existed, but I think they deserve their own thread.


Anyone have experience using them?

In Energy efficiency and durability | Asked By Scott Wilson | Apr 17 18
2 Answers

Ceiling insulation

I live in South Florida and have an uninsulated open ceiling in a laundry room that used to be an outdoor laundry, it has since been surrounded by a finished living area. It is open to the roof with 6” trusses on 16” centers. The room has a block wall on one side and stud walls to the ceiling on the others so there is no way to vent the space from eaves to ridge. It gets very hot in there and I want to insulate and drywall the ceiling. Should I fill the joist space with insulation or should I leave a gap between the insulation and the roof deck?

In Energy efficiency and durability | Asked By TomProud | Apr 18 18
17 Answers

Wall insulation for a new room addition

I'm thinking about this (not so) future project. One option is 2x6 studding with R-19 (6") fiberglass batts in between studs. To gain more R value and reduce thermal bridging I was thinking of adding probably 2" of type II EPS (4.2 R per inch they say)to the inside of the studs, for about R-27 for the wall. I'm assuming this needs to dry to interior since plywood and/or OSB are pretty impermeable to moisture and would limit drying to the outside. Is that correct, and if so is 2" of EPS adequately permeable for interior drying? I would have sheetrock over EPS.

In General questions | Asked By Howard Gentler | Apr 16 18
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