Why would this place not be insulated?

I did an inspection of the townhouse end unit today. I normally see the party wall between two units not insulated at all. However as you can see at this picture only a small portion in the middle of the wall was not insulated. This really puzzles me. Why?

Hey, Yuri.

I’m finding your post a little confusing. You normally find the wall “not insulated at all,” so are you questioning why they are not insulated, or are you questioning why this one has insulation? Adding insulation won’t hurt anything. That middle section looks like concrete, which normally isn’t insulated.

Hi, Russel:
Thanks for your reply. I felt that it will cause confusion. Sorry about that. I only mentioned that normally the interior party wall between the units is not insulated at all. In this case it was. But my question really was about the missing spot in the middle. If you say that it is concrete, then the whole foundation wall is concrete. If the builder decided to insulate the party wall in this case, why was he so selective and left a middle portion uninsulated? That was an intent of my post. Thank again.

I see. In looking at the picture more closely, I see what you’re asking. I actually thought the insulation was in the wood framing and that the concrete in the picture was the only concrete present. So if the whole wall was concrete, I’d say that he just ran out of insulation batts. He probably bought them by the case and fell one short, and Home Depot wouldn’t sell him just one.

My guess is the concrete company ran out of 4 foot forms and thru in a couple of 8 footers to finish the job.
Is it a walk out basement?

Are there future use provisions on the print for a person to buy two units, and connect them with a door? I’ve wired a few condo and townhouse buildings where I had to keep wiring out of certain spaces due to planning and provisions for a doorway to connect two units. That may explain the missing insulation. Just my best guess.

The basement is not a walk out. This is an end unit of the townhouse complex, and the wall in question is the common wall between two units. Marc, you may be very well right on your assumption. Since this is a brand new townhouse, and the insulation obviously was made by the builder, I would think they planned something like a door in this place, but changed mind later. In a hurry they forgot to add insulation, and that what I was writing up. Thanks to everybody for replies.

‘Common Walls’ are not required to be insulated at all under most energy codes.

Only walls that comprise the ‘thermal envelope’ of a dwelling unit need to be insulated. The ‘thermal envelope’ only involves walls to the exterior or walls that adjoined unconditioned spaces.

That said, a ‘common wall’ between conditioned dwelling units of a townhouse do not qualify as walls comprosing the ‘thermal envelope’ and do not need to be insulated under any energy code.

Insulation ‘may’ be used for sound deadening or other purposes…but insulation is NOT required between townhomes.

This is the best reply I have seen. And the most logical.
IMO the installer realized[or was told ] that he didn’t have to insulate this section of the wall and instead of removing the insulation he left it minus the 3’-4’ section. He did this just to confuse the HI:mrgreen:

Having a door between the two town homes …I don’t think so. I have seen Condos Marc that have provisions for a purchaser to buy two units but never Town Homes.

Yuri sometimes you have to look at the simple answers, You have done at least both of your Part 9 courses and you know that no insulation is required on this wall.

Mario, if you re-read my first post, you will see that this is exactly what I mentioned. Party walls usually do not require insulation. However, as RR stated, insulation never hurts, but why to do it in such a strange way?