1910 semi - how thick is our connecting wall to our neighbours

[SecondaryBurnzzz]

Hi there 👋🏻

We are in the process of putting up some bookshelves in the alcove of or lounge. The instructions suggest affixing the unit to the wall using a screw and rawl plug. The depth of the whole wood that the screw has to get through is 63mm. I don’t know what length screws I need to use. I can hear our neighbours telly through our adjoining alcove so the walls can’t be that thick. Obviously I don’t want to drill through to their side of the wall, but also don’t want my book case to fall down. What do you think? The people on Wickes seem to be a bit unsure so I thought I’d ask the experts on mumsnet.
Thanks 😊

The wall will be either 9 inches or two skins of 4 inches each. Plus any plaster or plasterboard.
You would only need to go 60-70mm in to the brick to get a very strong fixing.

It will be two bricks thick.

That’s good to know John thanks. So I the screws would need to be around 120mm long? 63mm through the wood and 57mm for the wall.
Thanks 😊

Thanks listening much appreciated.