Insulating and renovating - advice and options?

[Cloudscape]

We have two rooms that are referred to as the 'hay loft', because they are above the stable and coach house. They've been used for storage for the last 20 years, but were in regular use for a long time prior to that (as proper rooms - one as a living room and band-practice room, the other as a modelmaker's hobby room).

The roof is about 15 years old. Rafters are 2" x (less than) 4". Please try to ignore the nasty cement work around the purlins and the hayloft doorway. The insulation poked in at the base of the roof was a quick way to stop birds using the roofspace. I know it shouldn't be there.

The rooms are not accessible from inside the house. Current access is by a ladder outside - there used to be a wooden external staircase, until about 15 years ago. The rooms are lovely - 12x14ft and 12x16ft.

We really want to bring these rooms into use. We're applying to put a staircase in.

I'm more concerned that these are two of the least 'tinkered with' rooms, and we don't want to spoil them. We like the feel of the rafters overhead, so I was thinking of adding timber to each rafter, to give us enough depth to insulate and plaster between them. A roofer said this was possible.

Then I spoke to another roofer/joiner, and he said that we should insulate between and over the rafters, board it out and skim. There are two smaller rooms in the house where they have done this and the featureless perfect plasterboarding is really not what this house is about. So he suggested fixing fake rafters on top of the board. :?

That's when I got depressed.

I don't really like the idea of a smooth featureless plastered ceiling. If this was done, would you add some joists across to create a horizontal ceiling (part way up the rafters) and to create a triangular roof void?

I'm aware there are building regs, but... if there weren't... how would you approach renovating this space so we wouldn't freeze in winter and bake in the summer - AND so that a lot of the character is maintained? The rooms would probably be in use a lot, as an office, where we spend most of the day and evening.

The floor is pretty good with quite a few wormholes. One room has regular floor joists, the other has branches and bits of tree for floor joists. These just need a bit of packing replacing. I was thinking of batoning the floor, insulating between the battens, and boarding again on top. Is this a good approach?

 

[Flyfisher]

Not sure if there are LBC and budget considerations (although I guess there are always budget considerations), but if you like the current interior of the roof you might consider doing the insulation work from the outside. Strip tiles and felt, board the roof, counter batten for sufficient depth to add insulation, re-felt, re-batten, replace tiles. Quite a lot of work though.

 

[Cloudscape]

External insulation isn't something I'd thought of. I don't think it's an option though. The roof follows on from the roof of the house, so we couldn't raise it. The budget is a consideration (sadly), but even if it wasn't I'd like to see how little we can do to make the rooms useable, keeping as much of the feel as possible. I suppose the roof and insulation are what we're mainly stumped on.

 

[Ian Bond]

Can you not insulate between the common rafters, and perhaps over them too (counter-batten), board and skim with a lime finish but leave the bulk of the purlins exposed?

This way you'd keep the nice roof shape and have some exposed beams.

I wouldn't stick fake timbers anywhere though.

Edit - this was probably what your joiner suggested, except it wouldn't be plain and featureless if you kept the shape, exposed purlins, and had a characterful lime plaster finish to the ceiling, decorated with limewash.

 

[Nemesis]

Consider a ceiling made from wood planks.

 

[Cloudscape]

board and skim with a lime finish but leave the bulk of the purlins exposed?

That is what he was suggesting, I think, but with a gypsum skim, of course. What would you board it with? The purlins would probably do for a 'feature'. The coach house and the stables (especially) downstairs are so characterful, they are a lot to live up to.

Consider a ceiling made from wood planks.

That's an interesting idea. Has anyone got any examples of this?

 

[Nemesis]

There's one above my head...

 

[Penners]

Here's an example. Not my cuppa tea, I must confess.

 

[Ian Bond]

I've used riven lath, but it's pricey - saved on the labour though as I do it myself.

However, there are a few more ideas on this page for alternatives to lath:

http://www.periodpropertyshop.co.uk/acatalog/Plaster_Backgrounds.html

I think Gervase used reeds for his ceilings...

Then again, Nemesis's idea of planks (bead and butt?), perhaps painted sounds very good to me. Rather a different proposition to orangey, varnished T&G "vee" boarding.

 

[Nemesis]

Yes, mine is T and G floorboarding, painted white with a very basic emulsion, although lime or distemper could be used.

It's on a sloping ceiling, with insulation under.

 

[Ian Bond]

Sounds like this one's solved for you then Cloudscape - I'd go for planks as per Nemesis's suggestion myself. Would suit the building perfectly and slightly easier than trying to plaster it all.

How did the rewire go btw - I seem to remember an electrician was insisting that your sockets were placed half way up the wall?

http://www.periodproperty.co.uk/forum/viewtopic.php?f=1&t=8648&p=104008&hilit=socket+height#p104008

 

[Nemesis]

We have a very similar hayloft and I think it's possibly what we will do there too.

 

[Lime]

A problem with using boarding, tongue and groove or similar, is that it can allow draughts to blow through it.
Of course it does depend on location, exposure, fitting and sealing.
However in a house I once had with this type of ceiling every gale brought dirt blown in.
It was not very nice.

 

[Cloudscape]

Butt 'n' bead is a nice idea. I've a couple of walls I was considering it for. All I need to do now is find a source for it. I'd probably limewash it - but I must say, the idea's cheered me up after the roofer/joiner's suggestion of fixing fake rafters. Thank you, Nemesis.

I'm guessing that the right way to do it is to insulate between the rafters (with a 50mm space for ventilation), then insulate over the rafters and fix the planks as a top layer? Is it too daft to consider adding to the depth of each rafter, insulating between, and then fixing the butt 'n' bead on top? Is thermal bridging a big problem? I hadn't thought that the ceiling might 'leak' air. I wouldn't have envisaged any gaps.

The rewire's the reason why I've fallen off the planet somewhat. We're about 2/3 of the way through, and the old wiring is so interwoven that the electrician can't proceed unless the kitchen goes and we also take out a bathroom - don't ask. We've taken this as an opportunity to have a breather and to get our energy and motivation going again. The disruption and mess has been pretty awful.

And despite everything I said, the sockets and switches have carried on being fixed at interesting heights.

Now we're stuck on the kitchen. We can't find a sink we like. :?

 

[Nemesis]

Not at all sure how boarding can blow a gale through - mine certainly doesn't! The T and G fits together and it's insulated under. The only draught comes around the frame where there is a cast metal rooflight, but that simply needs filling.

Do make sure the wood is well dried, it still can a shrink a bit, but all adds to the rustic charm etc.

 

[Ian Bond]

I'd still probably go for boarding the ceiling. By the looks of it, your roof is felted underneath the tiles, which will cut down on some of the draughts and dirt. The layers of insulation should act as a further buffer.

However, I've remembered the following article, which may be of interest to others (or in case you can't use boards for some reason).

http://www.buildingconservation.com/articles/pdf_roofsbreathe/roofsbreathe.pdf

Scroll down for a Case Study dealing with breathability and insulation of an historic roof. I found this whilst I was researching repairs to my own stone roof...

 

[Cloudscape]

There's definitely food for thought there. Thanks for that. I feel a little as though I am trying to run before I can walk. I'm having to make decisions on behalf of the house, without really having a full grasp of all the possibilities, without being able to judge fully what will be best for the building (let alone affordable and aesthetically OK) - and without really understanding the physics involved.

The felt is old-style and non-breathable. The slates are in pretty good order. Since the roof was renewed, the hayloft door has been open, the windows unglazed, and until recently, there has been a gap around the wallplate. So the timber's lived in luxury, with lots of ventilation.

I need to work out what layers I should be thinking of applying, of which materials, to produce the best result all round. I freeze and can't make decisions partly because I like the house as it is, with all it's shabbiness and problems. The last thing I want to do is anything that is harmful to the building, will result in backtracking, and which will smarten the place up too much.

 

[Ian Bond]

Sounds good to me. If in doubt - do nowt!

Well, not quite.

But there are so many miracle products out there, claiming to do wonders for your building. I try to err on the side of caution, and favour the proven traditional materials and methods that have stood the test of time. Not always possible, I know.

It's not too difficult to imagine how someone could smarten up those rooms of yours, and bring them up to 'modern standards', destroying the character and sense of age in the process. A lot more difficult to decide how to repair and make usable without losing the charm.

As said of Sir John Smith, Landmark Trust:

It was 1975. As we toured the building
out came the notebook. He took
copious notes, red or black, about the
individual importance of the rusty old
hooks and nails bashed into walls and
beams. His eye for detail was unerring.
Next he sat on the stone seat in the
bower. He measured and noted the angle
at which his knees were bent. About 15
years later the height was raised slightly.
The tour complete he said,“I think it’s
rather good, don’t you? It looks as if we
have done nothing at all”.
In the boot of his car my eyes lit upon an
immaculate demob suitcase. I knew that
I was dealing with a thrifty man. As he
left he fixed me with that mock serious
look and said,“Mr Crook, whatever you
do here you won’t actually do anything
will you”.
Chris Crook, Curator, Woodspring Priory

 

[Cloudscape]

Talking of "the individual importance of the rusty old hooks and nails bashed into walls and beams", I'm rather fond of the odd piece of wood with a coathook in the middle of it.



I'd like to do nowt, but I'm itching to be able to use these rooms.

 

[Ian Bond]

It's a work of art. Cleverly using the existing timber grounds, and what looks like a floorboard.

So's the window - not in that much more of a bad state than the one I've just mended.