ᐅ Building a Basement – Is Installing Exterior Insulation in January Advisable?

Hello,
we are building with a prefab house company, and their plan is to set up the house in mid-March 2023.
This means that excavation and foundation wall construction are scheduled—or have to take place—in mid-January 2023.
The prefab company also informed us that the (basement) insulation cannot be applied at the factory but must be installed on site.
When I asked our architect whether installing insulation under such weather conditions (estimated 0 to 8°C (32 to 46°F), rain/snow, etc.) is feasible, he replied:
“It could work, but it might not.”
My own judgment tells me this is not a good season to “stick” (attach) insulation to the basement walls.

What is the situation regarding the buyer’s or client’s rights—can you request to postpone the house assembly (and thus the start of foundation work/insulation) by about six weeks?
(In our case, foundation work was no longer possible this year because the final go-ahead from the prefab company only came two weeks ago, and it is very difficult to find an excavation contractor on such short notice.)

On what basis do you want to demand that?

You have the right to request a defect-free completion. When and how this is done, and how it is ensured, is up to the prefabricated house company.

Be glad that you are getting a house.

I’m still a bit confused about who is supposed to do what and when. Are you handling the basement yourselves or subcontracting it independently? Completely or just digging the hole? The insulation is done by the prefab company, right? (This is a bit confusing to me.) So, where exactly are the handover points at the moment?

As for the "right" and "demand," I’m not sure. But if you think you won’t finish your own work on time, you should obviously discuss this with the following trades well in advance. Worst case, if you say nothing, they might show up fully prepared to install the house and then have to leave immediately because it’s not ready yet, and you might still have to pay compensation for the whole effort.

There are many variables in the “might work” scenario.

First of all, how will the insulation boards be installed (with perimeter adhesive, mechanically fastened, hopefully not with waterproof slurry)?

Weather and temperature conditions regarding processing guidelines also play a big role, and this strongly depends on where you are building.

Additionally, everything must be backfilled so that the prefab house builders can erect their scaffolding.

But I think the temperatures should be sufficient for this for a few days at the beginning of March.

darksun schrieb:

What are the options for a buyer or client to request a postponement of the house construction (and therefore the start of basement work/insulation) by about 6 weeks?

You will have signed a contract for the construction of your house including the basement, correct? That’s how I understand your post.
The contractor is obliged to deliver a defect-free finished product. Whether the insulation of the basement is applied in the workshop, on the construction site in rain or snow, or on a mild spring night under a full moon, is entirely up to them. The only obligations they have towards you are to meet the agreed timeframe and to provide a finished product free of defects.

darksun schrieb:

This means that excavation and basement construction are planned or have to take place in mid-January 2023.

I think this is exactly what I find most confusing right now. Are you doing it yourselves or is the prefab company handling it? Everyone else here seems to have understood it as "the house builder does it," but I wasn’t completely sure about that. If the house builder is doing it, I would say it’s definitely worth asking if they are sure about the timing, but basically, that’s their responsibility.

If you are doing it (which is how I understood it), but you think that everything in January is going to be a complete mess or that you might not even find anyone to do it, then the basic requirement to continue working isn’t in place at all (but in that case, I don’t understand the whole argument about the insulation. Is that just meant to be a reason why the house builder should give you more time, without it being your fault?)