New Window Opening Installation and damp and support concernes

[Xlnc1981]

Sorry folks, having a bit of a panic.

Had plans done for a new window opening (ground floor level) to be made in addition to other work last year. The only remaining job was the window.

I found local builders who seemed reasonable and competent.

They’ve made the opening through an external load bearing wall and installed the stone lintel/ upvc window - seems fine.

However they’ve not fitted a lintel on the inner breeze block work and there has been no mention of any damp proofing.

I am concerned the inner block work above is unsupported and could damp come through without damp proofing?

Building control are yet to come out due to pandemic and I’m just worried as I’ve already paid the builders as they told me job complete.

Can somebody please tell me what I should have expected as a minimum on this type of install? Which would be generally compliant with building regs?

Any advice much appreciated.

Thanks

[stoneyboy]

Hi xlnc1981
If the opening is narrow e.g. a loo window they may get away without an internal lintel. If it's a wide opening hopefully they will have used an inverted T lintel but you may not be able to see it.
Regards S

[Xlnc1981]

Hi Stoney,

Really appreciate the reply.

The builders have told me they haven’t fitted an internal lintel - which means the inside block work is unsupported and they were prepared to leave it as that. The stone lintel outside in brick work matches the rest of the house.

Now building regs are saying an R9 lintel needs to go on inner leaf and the builders are saying an r15.

Obv, when I instructed them I expected them to work to building regs.

For a new window opening (upvc window is 1585mm wide) should they are done any damp proofing work before they installed the window?

Appreciate any further advice.

[stoneyboy]

Hi xlnc1981,
An R9 lintel would be appropriate for that opening and if you want BR approval that is what must be fitted.
Some form of cavity tray should have been installed with the new lintel. A problem with water ingress above the new window may only occur if rain is driven against the area above the window but you may be lucky that this does not happen.
Regards S