june melton
10/14/2013
We are building a straw bale house which will be heated with both electric heat pump and wood burning stove. We plan to use 26 guage metal on the roof, with no decking- just 2x4 purlins. The roof has an 8/12 pitch and is well vented. Part of it is made with a scissors truss, so we had our trusses built with an energy heel to allow for more blown in cellulose insulation. I have talked to more than one contractor, and get differing ideas about how to lay the roofing material. One says spray foam under the metal, another says use a rolled underlayment between the metal and the purlins that will hold moisture and release it back slowly, another says just lay the metal and use the blown insulation. We want to be environmentally conscious in the products we use, as well as financially conservative. But I also don't want to fail to apply an underlayment only to wish it was there later. We are in a very rural area with few contractors to choose from and no real regulations. I believe that everyone I have talked to so far has been trained by a company that is selling a product, and none seems able to give me a side by side comparison of different strategies or have specific knowledge of the requirements of our area. Please advise before I make a choice I will regret. Another issue is that some of the trusses are over both an open air porch and conditioned space. I know of a situation where this caused the trusses to expand and contract and resulted in a need for repairs later. Would the way we choose to insulate have any effect on whether we also experience this kind of problem, and if so, what do you suggest for that situation?
Info @windowsonwashington.net
An informed customer is our best customer.
10/15/2013
I am always a fan of putting rigid foam between the metal and the SPF. I also love above deck venting. Doing this would give you the thermal break in the roof and allow you to run less expensive insulation options.
Guest User
9/11/2014
does a metal roof save on heating cost in the winter months? Are their specific colors that are better for winter months, and specific colors that are better for summer months? I live in Iowa which is more of a cold state than a hot state. what do you think the year round energy savings could be? If their is not a big difference in saving between colors, I might chose a dark color, but could also go with a light color.
Todd Miller
Classic Products, Inc.
9/11/2014
Hi Gary, you have a great looking home! Generally speaking, the roof is not the place to achieve energy savings in the winter. In the winter, you're concerned about holding heat inside the home. Your heat source is your furnace (or other heating source) which is inside the home. That heat is held inside the living space by insulation. The attic, then, is (by building code) kept as cold as possible in order to avoid ice dams on the roof. Any heat gained through the roof from the sun is vented back outside. In rare instances based upon actual construction, trying to collect winter heat through the roof can be useful but generally speaking on virtually all homes, that is not the case. So, in your case, you may want a more reflective roof to help achieve summer efficiency but winter efficiency via the roof is rarely a legitimate consideration/opportunity.
Info @windowsonwashington.net
An informed customer is our best customer.
9/11/2014
+1 In a heating degree dominated climate, get the roof color that fits the look of the home. If you are relying on passive heating from the roof, there are bigger issues with the insulation schedule as Todd mentioned. Good looking home as Todd also stated.

If you would like to reply to this thread, please log in. If you do not have an Ask the Experts forum user account, create one here.

Find a Contractor

Get Started Today

Take the first step to increasing the value of your home with a great looking, durable, fire resistant and energy efficient metal roof. Browse our list of qualified MRA Member Roofing Contractors in your area for a free consultation and estimate.