Cleaning Loft - Waste of Time?

[mcprinter]

Moved some Insulation to see if there was anything going on linked to a crack in a newly skimmed Ceiling.

1930s House. Large 2 Storey Side Extension. Slate with Felt.
Insulation clean. We store a few Items at this end.

Original Part of the Slate Roof has no Felt. Lath and Plaster.
Insulation filthy and lots of very fine dust everywhere. Most of the Pointing? on the Slates has fallen off onto the Insulation.
Spent Hours picking up, brushing up and Vacuuming a very small area.

Only 100mm Insulation so I do need to add some more.
Am I wasting my time cleaning up?
Bin the old Insulation or just lay another 170-200mm over the Top?

Changing the old Halogen Downlights for LED
Do they still need the protective Boxes?

We have been here for 20 Years. Handful of Slates replaced and Chimney Repairs in that Time.

 

[Alastairreid]

If the existing insulation looks compressed and clogged with dust it will have lost some of its thermal qualities and would be best if replaced.
If the led downlights are fire rated they dony need hoods.

 

[richw]

I had no felt in my last house (also 1930s). I cleaned it all up, and within a few months, it was filthy again. So a total waste of time!

 

[Alastairreid]

The rafters can be lined with breathable membrane stapled on from ridge to eaves which would help..is it worth the bother though.

 

[Diver Fred]

The rafters can be lined with breathable membrane stapled on from ridge to eaves which would help..is it worth the bother though.

I'd say yes. Just make sure that the mortar doesn't overload the soffits. I'd also make sure you have a standing area around the hatch so that you can get into the loft and have a look around at times.
If you use the loft for storage then It's 100mm insulation on ceilings and 100 rigid on rafters.

 

[Alastairreid]

Insulating at rafter level would need ventilation issues taken into account.

 

[mcprinter]

Thanks for the replies.

I think I will replace the old Insulation and take it to 270 or 300mm.
I will not be using that Area for Storage. Cylinder and Tank make it quite difficult to get to anyway.

There are a few Boxes in the newer felted area. They stays pretty clean.

The Loft Hatch is under the old Roof but very close to the newer felted Roof.
I might look at adding something to the Rafters there to stop the dust collecting around and on the Hatch.

 

[datarebal]

https://www.loftleg.com/loftleg

 

[mattylad]

I cleaned mine, there was several very heavy rubble sacks cleared, all that weight on the ceiling could not have been good - then I replaced that weight with more of my crap

 

[RandomGrinch]

I cleaned mine, there was several very heavy rubble sacks cleared, all that weight on the ceiling could not have been good - then I replaced that weight with more of my crap

I cleaned mine as well, with a lot of effort getting big rubble sacks down through a tiny hatch.
Apparently (at least in my area), when grants were available for reroofing in the 80's, the contractors would just knock the whole roof down into the loft.
Hence some very mucky insulation, a loft full of slate dust, and the need for many rubble sacks!

 

[mcprinter]

The area I cleaned was a right pain
The Plaster lumps between the lathes made brushing up difficult.
My Titan Wet/Dry kept blocking up. Very slow going.

I was filthy and Face Mask was black. Nasty stuff Slate Dust apparently. Will get a pro Mask before doing any more.
Two Rubble Sacks and Two Vac Bags.

 

[Diver Fred]

Insulating at rafter level would need ventilation issues taken into account.

As the original poster has commented that the torching (pointing) is or has come off the joints in the slates I'd say there will be enough airflow to keep the timbers dry.
Certainly has in the family home - my old boy who was a C&J of many years standing didn't have any qualms about insulating on the underside of the rafters after the torching had come off. we check the roof timbers every 4 or five years.

 

[tell80]

mcprinter,
The back pointing you complain of is called Torching & its a fragmenting menace.

Its an old technique designed, so I was told, to stop drafts and slate rattle.
Once Torching has reached its fail by age, & wear & tear date then another problem can sometimes show - nail sickness, or the corrosion, & maybe failure of the original nails.

 

[JohnD]

if or when you decide to floor the loft, that's a good time to throw out the dirty old insulation, clean up, and lay new. It's much easier to keep a flat, smooth boarded floor clean. You can also put some kind of lining up if you want, though such an old roof may need replacing before long. The new one will have a membrane liner so will stay clean. I really like sarking boards but they are not common in England.

To add new insulation of deeper thickness, you may need to counterbatten the joists otherwise the flooring will crush it.

Loft legs can also be used.

p.s.
old dust may included deposits from industrial and domestic chimneys, and the insulation may be yellow fibreglass. I find the combination very irritant to the chest. A builder friend told me his colleague had a fatal asthma attack in a loft. So I would certainly mask up and clean it out.

 

[mcprinter]

mcprinter,
The back pointing you complain of is called Torching & its a fragmenting menace.

Its an old technique designed, so I was told, to stop drafts and slate rattle.
Once Torching has reached its fail by age, & wear & tear date then another problem can sometimes show - nail sickness, or the corrosion, & maybe failure of the original nails.

Thanks Tell

I had a bit of a read about Torching after wgt52 mentioned it.
Used in the Days before Felt to stop the Slates lifting in Strong Winds.