Hi, we have an old house (built around 1820) which we are currently doing up. On checking the plaster I've discovered many of the walls are blown (they sound hollow when tapped and some even move - oddly it's much worse on the internal walls than the external).
I started removing the blown plaster from one of the walls and to my dismay the whole wall was loose. I tried another room and it was the same.
I'm pretty sure the plaster is the original lime although I'm no expert. On the walls currently there seems to be a rough scratch coat about 5 to 8mm think with a coarse hair mixed in, then a thick coat (about 15mm but it varies a lot with the straightness of the wall) of a sandy material with a finer hair then a single skim about 2mm thick of a fine material.
My dilema though is that although it's not attached to the wall because of the hair it doesn't just just fall down. Once I've made a hole by say pulling out a nail I can pull chunks off with my hands but before I've made the hole it's wobbly but it holds together. Do I just rip off the blown stuff and start again or do I try to just patch the worst bits?
What I would like to know is what is the best way forward? The conservation people from the council have told me I've got to use lime everywhere but to be quite honest I can't afford someone to come and do it in gypsum so I certainly can't afford someone to come and do it in lime.
I'm a pretty good all round DIYer and I pick things up fairly quickly although I've not done much plastering to date. Is it worth me booking myself on a course for lime plastering or is it just wishful thinking that I could do it myself in lime?
Alternatively I could just use browning on the lot (or D&D) and be done with it. The walls have been extensively patched with gypsum in the past and none of it has cracked. Could I put a gypsum skim over the existing lime?
Sorry for the long post, this one has got me a bit stumpped.
I started removing the blown plaster from one of the walls and to my dismay the whole wall was loose. I tried another room and it was the same.
I'm pretty sure the plaster is the original lime although I'm no expert. On the walls currently there seems to be a rough scratch coat about 5 to 8mm think with a coarse hair mixed in, then a thick coat (about 15mm but it varies a lot with the straightness of the wall) of a sandy material with a finer hair then a single skim about 2mm thick of a fine material.
My dilema though is that although it's not attached to the wall because of the hair it doesn't just just fall down. Once I've made a hole by say pulling out a nail I can pull chunks off with my hands but before I've made the hole it's wobbly but it holds together. Do I just rip off the blown stuff and start again or do I try to just patch the worst bits?
What I would like to know is what is the best way forward? The conservation people from the council have told me I've got to use lime everywhere but to be quite honest I can't afford someone to come and do it in gypsum so I certainly can't afford someone to come and do it in lime.
I'm a pretty good all round DIYer and I pick things up fairly quickly although I've not done much plastering to date. Is it worth me booking myself on a course for lime plastering or is it just wishful thinking that I could do it myself in lime?
Alternatively I could just use browning on the lot (or D&D) and be done with it. The walls have been extensively patched with gypsum in the past and none of it has cracked. Could I put a gypsum skim over the existing lime?
Sorry for the long post, this one has got me a bit stumpped.