ᐅ Semi-detached house (single family unit)

Hello everyone,

we own a detached semi-detached house that was completed two years ago. The neighboring house is still for sale and has not been built yet.

I am wondering if the party wall is properly compacted/sealed... Can anyone provide some information on this? See photo...

Thank you in advance.
Aero84

That looks like a single-layer pumice outer wall shell, with an insulation board layer behind it. I’m not so comfortable with the insulation board edges being exposed. On the party wall, the insulation board layer appears to be the outermost layer, with a membrane attached to battens, which are further secured by additional battens to prevent flapping. It seems that one “section” is torn open—this definitely isn’t airtight. Was this done by a developer who plans to build an extension in the same way but only after selling the neighboring half?

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/

11ant schrieb:
This looks like a single-layer pumice outer wall shell, with an insulation board layer behind it. I’m not too comfortable with the insulation board edges being exposed. On the party wall, the insulation board layer seems to be the outermost layer, with a membrane installed on a battens framework, which is then secured against flapping with additional battens. Apparently, one “section” has come loose – that is definitely not airtight. Was this done by a developer planning to build an extension in the same way, but only after selling the neighboring half?

Thanks for your reply. Yes, the extension will only be built after the sale... Unfortunately, I didn’t quite understand the rest, as I’m not very skilled technically in construction. I will definitely ask about repairing the membrane... What exactly do you mean by the “insulation board edges”?

Aero84 schrieb:
What do you mean by "joint edges of the insulation layer"?

Well, you can see that behind the outer shell there is a layer of yellowish panels. The edge where the panels of the neighboring house will meet looks like it is not covered with anything. So, they can basically absorb moisture or weather over time.

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https://www.instagram.com/11antgmxde/
https://www.linkedin.com/company/bauen-jetzt/

Insulation absorbing water is bad because wet insulation loses its insulating properties and can rot, depending on the material. There should have been weather protection in place until the second half was added.

OT:
It’s really a bad idea to build semi-detached houses (oxymoron) with multiple builders involved. That’s the kind of project for a general contractor/developer.

@11ant
Fleece-faced rock wool, just a guess. On top of that, battens. Neither of them tolerate moisture well.

11ant schrieb:
Well, you can see that behind the outer masonry shell there is a layer of yellowish panels. The edge where the neighboring house’s panels meet it appears to be untreated. So they can basically "absorb" moisture and deteriorate.

Now it’s clear, thank you. I will raise an issue about this... I’m also surprised that the air gap between the exterior wall and the insulation isn’t sealed, as rainwater and moisture can enter there... But I’m not sure if this can damage the exterior wall?