Insulation
Denton
| Posted in Energy Efficiency and Durability on
I have a 1800 sq ft bungalow style house with cathedral ceiling that is 20 years old and has r36 insulation value when I built it. I am interested in topping it up to r60 and wonder if someone can tell me if there will be much energy savings. (I installed a heat pump and high efficiency furnace last year)
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Replies
Going to R60 from R36 is a gain of R24, which is about 67% more than you were starting with. You'll have around 40% less energy loss with R60 compared with what you had with R36, but in absolute BTU numbers, you're not likely to see huge amounts of energy savings -- but you will see some. If you're looking for a "does this make financial sense" type of argument, a lot of it will come down to how much it'll cost to do the job. If you can just blow in more cellulose in a big open attic, then it's likely to be a relatively inexpensive project.
I would probably do the project if it were my home, but I'd strongly consider going a little further and doing some extra air sealing too -- although if the house was built to code only 20 years ago, it's probably not too terrible. Many of the people on here are doing energy upgrades on houses built in the 70s or earlier, back when much less attention was paid to insulation and air sealing details, so those homes have a lot more to gain from these kinds of projects in terms of energy savings and the associated cost savings that brings.
Bill
Thanks for the information. I appreciate it.
Denton,
Unfortunately the only way of getting a good idea of potential savings is by doing energy modelling.