Week 69-71 - Boarding out and Insulation of Bottom Floors

Now all the wiring and pipework is safely cocooned inside our walls and ceilings (on the bottom floor at least) we can stuff them full of insulation and plasterboard.

First we stuffed the internal walls and ceilings with what was once called ‘rock-wool’, although is now apparently ‘ECO-wool’. Don’t be deceived by the soft and fluffy appearance of this stuff. If you were to find yourself stranded naked in the Arctic with just a roll of this stuff to keep you warm – you would have to make the choice between freezing to death or scratching your skin raw.

It is however very good sound insulation to stop any loud workshop noise transferring upstairs to the rest of the building. To improve this further still we have used ‘Resilient bars’ on the ceiling to the underside of the residential area above. These are basically ‘Z’ shaped profiles of folded steel. Rather than the plasterboard attaching directly to the floor joist, one tail of the ‘Z’ profile attached to the timber joist while the plasterboard screws into the opposite tail of the ‘Z’. Allowing the plasterboard ceiling to vibrate independently from the floor joist, reducing sound transference.

We then boarded the ceilings with fire proof plasterboard (hence why it is pink). Because there is residential space over the top of a commercial area we have to achieve a 1 hour fire rating on the ceiling. Now to do this you have to put up 2 layers of ½ hours rated fire board… -what’s that I hear you ask: why don’t they just make a thicker 1 hour board?

It’s a fine question, and one I am yet to of received a satisfactory answer to. So if you are reading this and do in fact know of a good reason, please let me know, because at the moment it’s just double the time/effort/cost for (visually at least) the same result. If not: don’t steal me idea – im going on ‘dragons den’!

The joints in the boards are them taped and filled. This method is not as good as having the full ceiling skimmed in plaster but that would have been a cost I can’t justify for a workshop ceiling.

The walls are then boarded too. I have done this in OSB instead of plasterboard as it is much stronger and will take much more wear and tear in a workshop than plasterboard.

The external walls are filled with 100mm of solid foam (kingspan style) insulation and then counter battened to the outside wall studs and a further 50mm put in. As reference, this is a lot of external insulation, so should keep use very nice and toasty.

I then built the internal wall dividing the customer staircase up to the gallery off from the workshop

Stairs wall boarded out with door and 3 viewing windows reveals ready for later

The bike shed has also been boarded out and separated from the rest of the workshop. I have put a 2.4 meter internal ceiling on it to create some extra storage on top.

We have also pinned thin fire rated strips of timber onto the ceiling to cover up any screw holes and raw edges of plaster before painting