Expert: Ted Barnhill (Principal, Design45 LLC) - 10/29/2008

Question
QUESTION: Hi, I live in Fargo, ND so the climate is much like MN. We have a house that was built in 1890 and needs insulation. I think the R value now is around 3. We keep the heat around 50-55 in the winter and the bills are $300-$400/month. We are looking into getting the house insulated and sided. One seameless steel siding company told us that we would be wasting our money to get it insulated and should just use tyvek. What do you think?

ANSWER: Amy,

That is ridiculous!  I can't believe that there is anyone in the building trades in Fargo who doesn't believe in the value of insulation!

Proper insulation and air sealing will pay for itself, this is a fact.  If you have a leaky, drafty home, then caulking gaps and sealing windows (even if only with seasonal 3M shrinkwrap) is a must, and will pay for itself in reduced energy bills within the year.  If you have an open attic with poor attic insulation, then you can add blown-in cellulose, which will likewise save more than its cost within a couple of years.  Wall insulation is more costly to install, but if you are planning to reside, you should certainly add as much insulation as you can.  Some options, in order of increasing cost and effectiveness, are fiberglass, damp-spray cellulose, cotton, rigid board, and spray-foam insulation.  Spray insulation is the premium and best choice, and while its initial cost can seem high, it will save you the most per year, and over 5-10 years will have paid for itself.

These savings, of course, are not just good for you, but also help reduce the negative worldwide effects of high energy usage - political, economic, and environmental.  I hope you enjoy your newly-snug home this winter!  -Ted



---------- FOLLOW-UP ----------

QUESTION: do you think we should insulate and tyvek the house?

Answer
Yes, you should insulate the house and provide a good drainage plane behind your siding.  Tyvek is a common choice, though some healthy building experts now recommend building paper instead, as homewraps can potentially exacerbate moisture problems within walls if become less breathable over time.  If you have more specific questions about homewraps, please post a follow-up question.  Thanks, Ted