Mains, PSUs and other goodies.

[irving2008]

@Irving: The best way I can answer that is "no idea". I'm in the end-terrace for a row that go back about 100-odd years. I suspect they were built with the attics as habitable by design. Ours has actual stairs that look like they were meant to be there, and I note that all the other houses left from this row also have dormer windows - though ours were replaced with a bigger dormer at some point.



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Nice bench and a period chair too ;)

You should lift a floorboard or two and check the joist dimensions before you load the floor too much. A typical 100y old house would use 4x2 joists in the attic (my son's from 1903 does), they were never designed as habitable space but for light storage, tho it could be used for 'servants quarters' in larger houses, but the loading assumed very light (no heavy wardrobes etc.). Building regs differentiate between ceiling joists and floor joists. A 4 x 2 ceiling joist at 16" centres spanning a maximum of 8' (the width of a small room below) will support a dead load of no more than 500N/sq metre, an imposed (i.e variable) load not exceeding 250N/sq m and a concentrated temporary load not exceeding 900N. I'd hazard that you sitting at your substantial workbench is close to exceeding that.

Building regs do not allow for more than 1250N/sq m loading, above this they need structural design/calculations agreed by building control - this is why you need building control approval for loft conversions, especially where there is a wet room or bath installation (a full bath of water with a typical male in it is close to 2500N/sq m loading).

Again, don't want to be a spoilsport... but you don't know how the timber has faired over the years and it would be unfortunate for your new CNC build to end up in a crumpled heap on the floor below!