Wide expansion joints in aerated concrete

Hello.

We are currently constructing a new building (KfW40) with exterior walls made of aerated concrete (17.5 cm), which will later be clad with bricks after the insulation is applied. At several points, relatively wide (about 1 cm) joints have formed where cut aerated concrete blocks meet, which are currently still open. The site manager does not see this as a problem. The gaps will later be mortared on the outside and sealed airtight on the inside by plastering.

Is the occurrence of such joints already considered a defect, or is it unproblematic? Will the insulation be affected by this? Is the planned procedure for sealing proper? Or must a different approach be taken?

Thank you very much!

Hi,
there will still be an [WDVS] applied, right? Then it’s not critical. Statics don’t matter anyway.
What else should they do, cut a brick just for one centimeter?

Best regards,

Andreas

Yes, there will be insulation made of Styrofoam (160mm, WLG 032) on it. I do not expect 1cm wide slices. But can't the stones generally be cut to size?

You didn’t photograph the entire wall. Is the length of the wall perhaps exactly X bricks plus 1 cm?

Are there guidelines for... Dämmmörtel would probably be an option if the width is outside the norm (I'm just assuming that without knowing) but I wouldn't worry about it.

No, that happened because the stones were not cut quite precisely. In other rows, it fits exactly. Ultimately, there are also (still) not many joints that are somewhat wider.