Plasterboard ceilings are going up with recessed lighting

We planned to overboard the ceilings (meaning we leave the old ceilings in place and add new plasterboard over them) because the current old lathe and plaster ceilings (probably the original ceilings so well over 100 years old) are at the beginning stages of falling off in some rooms!

Near enough anywhere the previous owners had run water pipes over a ceilings we find problems, since this is an ex guesthouse with running water in most rooms this means most ceilings have problems!

The plan was to find the joists by sticking a spike or screwdriver through the old ceilings until it hit a floor joist above, then mark off where the joists are so when we screw the new plasterboard in place we hit solid wood (the joists) rather than fresh air (which apparently doesn’t hold screws too well ) Over boarding was a tip from a neighbour who has used this technique successfully.

Great plan except the ceilings are highly unstable in some areas and the act of sticking holes in them resulted in further, significant damage. For example large chunks fell off on the very first room we did!

I realized if the ceilings are so weak they can’t take me poking a few holes into them they are highly unlikely to hold up to us screwing around 100 screws per ceiling, I could see the ceilings giving way as we added new plasterboard and this would add a quite a lot of weight to the new ceilings. Even if we did manage to get the new plasterboard up, if the old ceilings do give way the weight could damage the new boards.

Better safe than sorry, so it looks like most of the ceilings will have to be pulled down.

Top floor already had the ceilings removed because of leaking flat roofs, so that’s 4 ceilings already removed. Last week I removed a ceiling from the second floor.

Using an old broom I removed an entire ceiling in about an hour. Since it’s the old lathe type ceilings I found a quite easy way to demolish them (lot easier than removing plasterboard). Create a hole big enough to fit the brush end of a broom. Insert the broom and pull at the wooden lathes, this quickly removes the wood lathes and the plaster without much exertion.

Removing one of these ceilings creates a LOT of dust, so put some tarps on the floor to catch most of it and wear a decent mask or your snot will be black for a week

Also helps to wear a baseball cap and protective glasses since bits of wood and plaster some how find there way to your face a lot!

After cleaning up and removing nails from the joists which took a lot longer than removing the ceiling! we decided to add insulation and recessed lighting since we had full access now.

B&Q are selling boxes of 10 value recessed lights that are 50 watts each for £25, so just £2:50 a light!

The first room we did is approx. 2.3M by 3.3M with a high ceiling, the wife thought this would need 10 down lights to cover everything, but I made an executive decision (she wasn’t at the house that day ) that 5 would be enough: one in the center, four in the corners ~65cm from the sides of the room.

Fortunately I was right, 5 was enough (whew). Note: a lot of these recessed lights are rated at 10 watts, if I’d have used those I think the wife would have been right (needing 10), but with five 50 watt bulbs it easily matches a standard 100 watt light bulb.

Anyway, I laid the wiring for the recessed lighting by replacing the current light rose (think that’s what you call it) with a new junction box (cost less than £2 from B&Q). Then using 1mm core wire linked the five lights together.

Started at the center with the new junction box, short piece of wire to the first light, another piece of 1mm core wire goes to the next light and so on until all lights are linked. Doing it this way (in parallel) means each light receives full power and more importantly if one light in the chain blows the others still work. If you link lights in a daisy chain or in serial (as suggested in the instructions with the lights we purchased) if one light blows none of the remaining lights work (same as you get with old Christmas lights).

Where ever the wiring needed to go between the joists I drilled a hole to feed the cable through. I cut a 16mm hole so any heat from the cable could easily dissipate. Also used cable clips to hold the loose cables against the joists.

After that we insulted between the joists with rolls of fibreglass insulation. We insulated internal rooms (they don’t have an outer roof above them) for two reasons. One it will slow the loss of heat upwards and two sound proofing. We estimate adding 170mm on insulation has reduced the noise by over 50%! That reduction is well worth around £30 per room and a little itching

Then we added plasterboard. The hardest part about this is lining it up with the joists, we are using 1800mm by 900mm boards (12mm think) because the wife and eldest son (14yrs) aren’t strong enough to handle the largest 2400mm by 1200mm plasterboard also I don’t think we’d get boards that big up three flights of stairs.

This means a little planning is needed and the addition of more wood to the joists. The first ceiling we did one of the joist was off just a couple of center meters, so nailing on a bit of 2″ by 3″ wood was enough to allow us to screw the plasterboard to the ceiling securely. The second ceiling we wasn’t so lucky and for that one we added noggins between joists. basically a noggin every 450mm so we got three screws into the edge of each 900mm plasterboard (I got to use my new Redeye circular saw cutting noggins ).

After that we cut 65mm diameter circles through the new ceiling for were the recessed lights come through, attached the bulbs and slotted them into the hole to finish.

That gave a ceiling that requires the joins sealing and either dry lining or skimming (not decided yet).

So far the cost per ceiling, inc. plasterboard, screws, lights and insulation is around £70 in materials.

Will add some images soon.

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