Wet plastered wall - Fixings for shelving - 1900's Property

[benzini]

Hello everyone,

I recently became the owner of a house built in 1905, by far the oldest property I have ever lived in, so I'm slowly getting to grips with the construction methods that were used at that time and the fun and games that come with owning a property from that era ...

My project this month is to add some shelving in an alcove next to a disused chimney breast, I've drilled a 5mm test hole to see what I've got to work with, it appears the wall has been 'wet plastered' (as in plaster applied directly to the underlying brick) there seems to be around 1-1.5 inches of plaster before the drill hit some resistance, which I assume is the brick. I know I'll need to drill into the brick to get a decent fixing to support the weight of items placed on the shelving, the shelving brackets I'm using have pre-drilled holes that will accept up to a 5mm screw - IKEA Bergshult / Granhult.

What type of anchor/fixing should I use in this scenario? The shelving can support up to 10kg

Would an anchor/fixing alone be enough or should I be using a resin too for extra support/strength?

Am I crazy to even attempt attaching shelving to a wet plastered wall of this age, should I be looking at free-standing options instead?

Any advice, suggestions, links to anchors/fixings gratefully received!

Many thanks in advance,

Ben

 

[Mr Chibs]

I think you just want some zinc plated (not gold ones) wood screws and rawl plugs. Nothing fancy, they will easily hold 10Kg.

Something like 5x70mm, so this will go in the brick by around 50mm (you can go longer if you like).
Don't use flat head screws, posi or torx.
Use a 7mm drill and rawl plug

There was no plasterboard in 1905, so internal walls were effectively rendered.
Your walls are probably 9" thick as well.

 

[benzini]

Thank you Mr Chibs, very much appreciated, will get some supplies and tackle this over the weekend!

 

[mrrusty]

Exactly as @Mr Chibs says. You don't need anything more than longer screws and plugs set in to the brick and not the plaster. If the shelves are full width a small batten under each end will help.

At risk of starting a debate, I always use schneider Thorsman TP2 and TP2B plugs in both red and brown - used them for years and still prefer them over all others.

 

[Harry Bloomfield]

I would suggest tapping the plaster before starting to drill, because often - plaster of that age might well have come adrift from the wall itself. If it sounds hallow, it will be loose, and will need extra gentle care whilst drilling.

 

[mrrusty]

it will be loose, and will need extra gentle care whilst drilling

Totally agree! Having recently finished a substantial refurb on a 1902 my experience is, if you have a lot of hollow sounding plaster, then really you need to drop it and re-do it either with traditional plaster or boarded. If it's a small isolated patch in an otherwise sound room, I probably wouldn't bother if the plaster isn't also cracked.

It'll be quite thick and quite likely with horse-hair strengthening - quite substantial and not so much different to plasterboard which after all is just plaster reinforced with cardboard. It will hold itself together to some extent. It is also possible to remove a small loose area and patch-plaster.

A room full of dropped plaster makes a heck of a lot of rubble and dust!

Am I crazy to even attempt attaching shelving to a wet plastered wall of this age, should I be looking at free-standing options instead

If you have a free-standing option with no other downside then I would consider it. If you can support the ends of an alcove shelf you'll probably be OK because the fixings are in shear. If you are relying on cantilever brackets it can be challenging, because besides the plaster being not that hard, the mortar between the bricks will also be soft, and murphy's law says that the fixing in tension on a cantilever bracket misses the brick and aligns perfectly with a soft mortar joint you struggle to get a fixing in...