Removing ceiling - exposing the joists and rafters

[DavidB]

Hi

I have a 1790s Grade II cottage. The bedroom ceilings are low and not straight. One bedroom ceiling was starting to come down - so I dismantled it before it fell. Now its all exposed I'm thinking I might try and leave it that way - looks nice. I've reached out to the CO and asked their advice on my plans before filling in another LBC application form (the last one took 7 months to get processed and approved - not sure my teenage daughter, who's bedroom is most impacted, is going to wait that long). Worse case I could simply whack up new plasterboard and effect a repair and move on if I don't get permission.

The current configuration - walls rise up 2 feet from floor with exposed studs and wall plate infilled with plasterboard. Then plasterboard between the rafters so they are exposed and that slope in and rise to a height of about 6 feet and to the plasterboard ceiling suspended on ceiling joists. Above the ceiling the rafters continue to rise up a further 4 feet until the ridge beam - so in other words a small loft space above the ceilings - I don't use any of it for storage - just water tanks above the bathroom. Most rooms run in series i.e. long thin house.

Options I am considering:
1. Just use the same type of insulation (glass fibre between the roofing liner) and continue with infill plasterboard close to the ridge beam and infill panels either end of the room to close them off from the neighbouring room. This would leave the ceiling joists exposed - I call them ceiling joists because the current ceiling are attached to them - but really I should probably call them collars - which is what I think their original purpose was.
2. Would I be better using lath between the rafters rather than plasterboard and then use lime plaster. My preference would be to use something like wool for insulation because it is light and flexible and less nasty than fibre glass and easier to shape around the irregular rafters than kinspan. But I'm worried all that oak lath up in the attic would cause the rafters to sag (even more). Secondly I'm worried that the fact the rafters are at an angle i.e. not vertical studs! that when I come to plaster them the plaster wont form good nibs because the insulation effectively laying on the laths.
3. If I did go for lath and lime up in the rafters should I remove all the existing plasterboard and lath and lime it all down to the wall plate. Or should I try and install some kind of edging plate and leave the existing plasterboard intact below that edging plate and use lime and lath above. i.e. this would be an edging plate between each rafter and at the height of the existing ceiling.

As I say I have outlined my plans and options to the CO, but I'd like to get a view of what others have seen, done, recommend.

Thanks,
Dave

 

[Gareth Hughes]

I'll come at this from the point of view of authenticity and say that, in my view, it's unlikely that a cottage of the 1790s would have had exposed ceiling joists. Furthermore, since you've removed the existing ceiling without consent, it's going to be down to your CO whether you get away even with that (it is an alteration that affects the character of the building, and thus a criminal offence), never mind what the replacement is going to be - it's possible that plasterboard is not going to be an acceptable substitute.
And knowing another regular here had a similar problem with their dining room ceiling - it appeared to be on the point of collapse but was actually carefully put back in place at a lower cost than the quotes they'd had for pulling it down and replacing with modern materials - I can't help thinking you might have made what could prove to be an expensive mistake.
Sorry to be so pessimistic.

 

[DavidB]

Hi Gareth,

Thanks for the warning. Sorry about this lengthy response - I feel I need to explain more. Although I am confident that no criminal offence has taken place. The existing and failed modern plasterboard ceiling was removed only after inspection to confirm and record the materials and checked with other rooms. Now is a good time to consult the CO as I am not yet altering, but simply mid-repair and considering options.

Option 1: like-for-like repair - I could have a new plasterboard ceiling installed and skimmed in a weekend and it would be back to how it was previously.
Option 2: lath and lime ceiling (there is evidence on the collars/ceiling joists that a lath and lime ceiling was installed at one time from the stripes on the wood - but that's just a point in time and not to say how it was originally constructed). This would be classed as a change of material although not altering the character, but I expect the CO would see it as a heritage gain and I would anticipate getting approval for this subject to details on the materials, fixings, application and finished decoration.
Option 3: leave the collars/joists exposed i.e. no ceiling and continue the infill to sloping rafters up to the ridge beam. Currently these are in-filled with plaster board up to ceiling height - I could continue this infill on the newly exposed roof using plaster board. This would alter the internal character and I expect this would require some convincing before permission would be granted. I wouldn't start this work until LBC was granted.
Option 4: same as option 3 but using something more traditional - like lime and lath. Again still an alteration and would be a change of material and character. The CO might see the use of traditional materials as a minor heritage gain and might prefer the sound of this option over option 3, but I expect I would have to push my case strongly to get that approval.
Options 5 / 6: would be to plaster over the newly exposed rafters - rather than in-fill and either with plasterboard or lime and lath. This option might be recommended if a cold roof was seen as more preferable i.e. less condensation behind the plaster than a warm roof as in options 3 / 4. Given that the condition of the existing exposed rafters looks identical to the newly exposed parts of the rafter in the loft - I don't think condensation behind the plasterboard is an issue. So the only advantage of these two options is that I could have slightly more insulation and could avoid installing batons. But would introduce an inconsistency in styles.

Option 1 is possibly more like it has been since mid 20th C and may pre-date the grade II listing (1970s), Option 2 would probably replicate what it was like in the mid to late 19th and early 20th C and option 4 is probably closest to the original internal decoration, but still an alteration.

My personal preference would be option 4, followed by option 3, then option 2 (these all being subject to LBC approval) and lastly option 1 which I am relatively confident that the CO will advise would not require LBC and would be classified as a repair - I'm not keen on options 5 / 6 due to the inconsistent aesthetics it would introduce.

Like you I also wondered if the ceiling joists/rafters would have been originally exposed. What I could add here:

1. The building was originally a work place and of modest construction. I think the upper floor was probably a storage area and there may not have been ceilings.
2. I called them ceiling joists because a PO has used them to attach the plasterboard ceiling to. I think that maybe they are more like collars than joists? One of them (the largest one) still has bark on it and is connected to the purlins with wooden pegs (square pegs in round holes) and has distinctive saw marks. Whilst others are much smaller construction and attached using rose head nails and look much smoother as if machine sawn or planed. I wonder if the large central one was the original and the others were added at some stage to counteract roof spread or rafter sag. Or simply added so that a ceiling could be installed (if so they didn't do a great job as these joists/collars are all at different heights and hence why now the plasterboard has pinged off them under strain of being bent).
3. Several of the newly exposed rafters in the loft appear to have been painted with either limewash or distemper - what is left is quite contaminated with dust and soot. It is well worn off now, but in some corners and crevices it is clearly visible. I have found similar patches of this cream / off-white powdery paint in other parts of the house under modern paint that has peeled off including the ground floor. This seems to indicate they were exposed at some stage.
4. The listing describes the buildings as "One storey and attics". I wondered if this also suggests that what are the bedrooms now with a small loft above where just attic storage areas originally.

So back to the original question, what would be better - lime and lath infills up to the ridge beam or plasterboard instead? If the former should I also propose to replace the existing plasterboard infills and lastly will I get a good bond on the nibs if I am plastering on a sloping surface with insulation resting on the rear face of the laths?

Thanks.

 

[88v8]

...will I get a good bond on the nibs if I am plastering on a sloping surface with insulation resting on the rear face of the laths?

If the insulation is soft - wool bats - and not stuffed in tight, there would be no problem bonding through the lathes.

And imho, the intrinsic unrelenting flatness of plasterboard has no place in a period house.

Ivor

 

[DavidB]

Thanks Ivor. The PO has tried to deal with your concern of flat plasterboard they have applied a brushed finish to make all the plaster look like rough lime application with horse hair - they have even added sharp sand in places to give it a really textured finish. However, having used some lime plaster and lath to restore a shower room, my view is nothing can beat that stuff and it just somehow looks softer and more sympathetic even when painted. Especially when used in combination with a nice timber.

Re the lime plaster onto sloping roof with insulation... thanks for confirming that - once I get some feedback from the CO and if this looks like an option, then I will mock up a small section and test it out. I already have materials left over from another project. It will be good practice and will only cost my time and effort.

 

[Flyfisher]

And imho, the intrinsic unrelenting flatness of plasterboard has no place in a period house.

We've discussed this many times before. Why do so many people assume that period houses always had wobbly plaster work? There is absolutely no reason for newly applied lime plaster to be wobbly and it is perfectly easy (well, for a skilled plasterer) to create a wall or ceiling of 'unrelenting flatness'. Indeed, why wouldn't the original lime plaster not be unrelentingly smooth and flat?

If you like wobbly plaster then that's perfectly fine, but let's not pretend it is somehow more authentic than a perfectly smooth finish. To suggest so is to insult the craftsmen of old who built the period houses we all enjoy so much.

 

[DavidB]

Flyfisher, I understand that the building that is now my home was originally built by the locals who used it - I don't think they would have been master craftsmen. I think they would have been the very poorest in society as well as the infirm and unemployable and probably without skills other than labouring - mainly farm labouring. That said I expect the organisers/benefactor pulled in a few knowledgeable villagers to help direct and guide and possibly do some of the work.
When I retire I shall do some research into that.

 

[Flyfisher]

That's a fair point; not all period properties were of the same status and a range of craftsmanship is always to be expected.

However, even though I'm nowhere near a competent plasterer, I can achieve a pretty smooth finish with lime plaster. Where I struggle is with things like float marks rather than flatness per se, probably because I'm not skilled enough to get things right first time and end up 'messing about' with the finish. Even so, I can certainly do better than the wobbly plaster we have on many of our ceilings, which are more the result of moving or failing laths than the original plastering work.

All the wobbly plasterwork I've seen has been due to historical movement of the underlying laths, either through failure of the nails (usually by rusting away) or by the underlying timbers moving and I think it would be pretty difficult to replicate the effect, even if I wanted to.

Of course, it is possible to create uneven plasterwork and if that's the objective then that's fine- and there are many examples in 'ye olde kit pubs' all over the land - but it just niggles me to assume that period plasterers were any less skilled than their modern counterparts and were not able to achieve perfectly flat wall and ceiling finishes.

 

[Me!]

Why do so many people assume that period houses always had wobbly plaster work?

I think it's because a lot of people confuse it with wattle and daub. I've got a few bits of wall that appear to be daub with many layers of limewash on them, and they are a very uneven surface.

 

[88v8]

And imho, the intrinsic unrelenting flatness of plasterboard has no place in a period house.

We've discussed this many times before. Why do so many people assume that period houses always had wobbly plaster work? There is absolutely no reason for newly applied lime plaster to be wobbly and it is perfectly easy (well, for a skilled plasterer) to create a wall or ceiling of 'unrelenting flatness'. Indeed, why wouldn't the original lime plaster not be unrelentingly smooth and flat?

If you like wobbly plaster then that's perfectly fine, but let's not pretend it is somehow more authentic than a perfectly smooth finish. To suggest so is to insult the craftsmen of old who built the period houses we all enjoy so much.

It depends.
We have a ? Georgian ? ceiling which is very smooth, but not flat. It perfectly follows the undulations of the joists. Plasterboard would iron this out.
The walls here are coursed rubble or timber frame. Plasterbard as wielded by the average builder would blandernise them.
It is too easy with pboard to cover up, to sail over, to flatten, to obliterate detail.
Period.... The walls of our 1920 house were flat and level and upright. So plasterboard would have been fine.
Most Victorian houses I guess had pretty decent plaster.
I dare say pboard has its uses. But it's a botcher's goto. Tabulum abhorrundum.

Ivor

 

[paulc]

We have a ? Georgian ? ceiling which is very smooth, but not flat. It perfectly follows the undulations of the joists. Plasterboard would iron this out.

Put some plasterboard up last year. Whilst the supporting timbers are fairly straight, they do not all sit at the same level and a couple are on the huh. Even after fixing up the PB and skimming, to the casual eye, it looks reasonably flat. But stick a straightedge on it, and the undulations are very apparent.

Plasterboard is cheap, quick, and covers a multitude of sins. But for a really flat surface, the supports need to be accurately placed and secured.

 

[Flyfisher]

It depends.
We have a ? Georgian ? ceiling which is very smooth, but not flat. It perfectly follows the undulations of the joists. Plasterboard would iron this out.
The walls here are coursed rubble or timber frame. Plasterbard as wielded by the average builder would blandernise them.
It is too easy with pboard to cover up, to sail over, to flatten, to obliterate detail.
Period.... The walls of our 1920 house were flat and level and upright. So plasterboard would have been fine.
Most Victorian houses I guess had pretty decent plaster.
I dare say pboard has its uses. But it's a botcher's goto. Tabulum abhorrundum.

I agree it depends. It depends on things like whether your ceiling was built perfectly flat in the first place or whether it now undulates because of historical movement over a few hundred years. The timber frame section of our house has so much historical movement that the floors and ceilings of some rooms are distinctly on the huh, nearly one foot across one of the bedrooms, which has caused all manner of undulations. As for our drawing room, the original timer frame and wattle & daub infill has indeed been covered up and flattened to obliterate the detail beneath, but it was done a few hundred years ago by nailing a perfectly square and level wooded subframe onto the original oak frame and then lath and lime plastering the lot, rather than using plasterboard - though the end result would be the same. Smooth, flat, square walls - which is what the Georgian's liked. So what constitutes truly authentic? Personally, I'd prefer to strip it all back to the original oak frame, but we wouldn't be granted consent these days. Besides, the large Georgian sash windows (for which the close-studded oak frame was hacked away when fitting) would then be a poor match. Having said all that, I do take your point about plasterboard. It does feel wrong to me compared to 'proper' plasterwork, but the lime plastering we've had done here is still smooth and flat.

 

[Tctc]

I know this is several years later, but we’ve come across the exact same situation as the original post. Wondering if original poster ever found a good solution or anyone else has some new found experience or knowledge on the old lath and plaster nail stains on our joists. If anyone even sees this…

 

[a twig]

There are quite a few questions in this thread, what exactly were you after a solution for? I can’t see any mention of nail stains in the original post..

 

[Tctc]

There are quite a few questions in this thread, what exactly were you after a solution for? I can’t see any mention of nail stains in the original post..

Goodness me, I somehow migrated amongst logging in. I’ll find the original thread I was after. Thanks for replying anyway

 

[Toby Newell]

Wow. I have found this thread very entertaining, here is my tuppence worth not being a historian but having worked on several hundred period homes and with not a little research along the way...

Exposed joists in 1790s cottage?

Absolutely possible. One has to understand there were two standards, those 'in town' and those in rural communities. Cheaper rural dwellings often did not follow fashions of the period and were of older, more basic designs. Only rich merchants' houses and manor houses would ape the more modern designs of the larger town houses. Thus it is much easier for me to be accurate in dating town houses than rural cottages via design, for the rural cottage I have to lean more onto the materials, the patination of such and any tool marks showing construction techniques.

As regards craftsmanship, many, many lols (so many lols) there was a hierarchy, certainly, in vocational trades, remember, before the industrial revolution most trades were 'vocational' but some more than others.

There isn't a lot of data to go on but in general, rural building trades were not paid exceptionally well and often there was not much difference between a good labourers wages and a skilled tradesman (as low as 30% for 'mates' ie learning apprentices - although there were 'general labourers' that mixed, fetched and cleaned who got paid a half to a third).

The highest paid were normally the toolmakers, the smiths. In the towns the highest paid were the stone masons and carpenters, the only real earners, apart from the business owners, were the artisans, the master craftsmen who did the decorative carving, insetting, decorative paint effects etc.

There would of been little advantage getting an infirm farm hand (many lols) to lime plaster your abode when you could get a very skilled craftsperson for only double the price (and thus probably double the efficiency for a better finish)

This would be akin to getting Tomas, the allrounder Polish builder (former taxi driver in his country) to rebuild your kitchen at £120 a day for 30 days, over a skilled kitchen fitter at £360 a day for 10 days... Not saying it didn't happen, but low skilled operatives have rarely been good VFM and the pay delta between mungo and a 7 year time served apprentice trained plasterer was less than that of today.

I don't think a lot of people realise that all you need to become proficient in a craft is mostly time and patience.

Most trades would start learning at age 10 or 11 (officially 12) and do a 7 year apprenticeship, so that on their very first day as a craftsperson they probably had better skills and experience than your average builder of today.

I have worked on many dozen properties over half a millenia old, wonderfully wonky and undulating, made partially from mud, horse poo, straw, sticks, lime and hair, from unseasoned green wood with no glue, fixings or proper foundations.

Having also worked on hundreds of new builds, including domestic homes and some of the largest projects in the country I like to think how many of these (RAAC anyone?) will still be around in 500 years...

The older I get the more I have become convinced, it's probably not the straw, the poo, the lack of foundations, damp proof course or properly dimensioned, pressure treated, C rated, kiln dried timber that is tje reason these structures are still standing.

Rather it was the general level of craft with which they were built.

The average craftsperson was of a level rarely seen today, that for me is a large part of the magic of period properties, they were, by and large, built by extremely skilled, dedicated and experienced humans who took extreme pride in their work (at least when compared to today) This is easy to understand, when your Grandfather and Great Grandfather did the same job and you've spent 7 years practicing before you reach 19, there is quite a strong inclination to do a good job.

Which is why you may hear me swearing out loud when I find subsequent butchery, laziness and stupidity that has been foist upon them that I have to remedy.

I am sure there were the occasional mungo's, but they were the exception rather than the rule, otherwise places lile Lavenham would not exist, along with hundreds of thousands of wonderful old dwellings.

It is absolutely possible to get a nice smooth surface with lime plaster albeit with gentle undulations, excessive settling, green timber and lack of laser surveying equipment meant few surfaces were mirror flat, smoothness and flatness are two very different qualities.

Just my thoughts.

CO's vary, there are those fascists who stick to the letter of the law, ie what is listed, is listed irrespective of age or period compatibility and those reasonable persons who are more inclined to go with the spirit of the thing. These welcome attempts at sympathetic restoration, restoration that attempts to change more modern listed details for more period age appropriate ones.

In general most enjoy being consulted, although it's always a good idea to find out which camp yours fall into as some are best left unconsulted... Perhaps ask around, if yours is reasonable then asking advice will bring brownie points and hopefully an agreeable outcome.

I have written expert opinions on multiple occasions, including for court, and have always had a positive result. Many CO's (and apologies to the those who differ) do not, in my experience, have much of a clue, the job is fairly low paid and study is mainly from books or university.

I have worked on landmark period buildings and projects worth millions and billions with CO's and advisors from EH who don't have the first clue, at least about my area of expertise.