Freezing in a granite cottage!

[billybob]

Dear All

We have recently purchased an old farmhouse built in the late 1890's from Aberdeenshire granite. The ground floor rooms all have what appears to be solid concrete floors, apart from the living room where there is a suspended wooden floor. This room is always freezing! Whilst investigating the plumbing in the house, after an incident (trust me, you really don't want to know!!) I lifted a few of the floor boards and the gale that blew up through the hole was amazing and direct from the artic. The house is in northen Scotland but blimey...........

I am considering removing the floor, insulating and then replacing the floor. Is this wise?

Also, the whole house internally is lath and plaster, some loose and hollow sounding, with no insulation anywhere. Having read through the topics on this forum there is some debate about the merits of stripping this and replacing it with framing and then insulating, with or without a vapour barrier then PB.

What should I do, ?

Help!!! I'm a bit confused, okay I admit it a lot confused.

 

[biffvernon]

Make sure you check the radon status before stopping the sub-floor gale.

 

[Nemesis]

Do you want a bland and featureless house stripped of its original lath and lime plaster and replaced with moden plasterboard? Not a great thing to do to a period building.

When you say all walls are lath and plaster, do you mean external walls as well as internal? Are all internal walls stud and plaster, or are some solid ones?

Presumably you have, or are intending to, insulated the loft?

The gale under the floor - are there a large number of air bricks venting under the boards?

 

[billybob]

Hi

At some point in the past the layout of the house was changed, several internal walls removed, the staircase moved and all the fireplaces were covered over. I am reinstating several of these fire places and during this process have discovered that the internal walls are a mixture of lime plaster, non lime plaster and PB!!!!!

I do agree, that a period home should be kept a traditional as possible, but I'd quite like to be able to sit in my living room in less than three jumpers, perhaps the floor is where the biggest heat loss is?

Yup, insulating the loft was one of the first things we did, I can't believe the previous owners lived in the house with absolutely no loft insulation!!

There are no air bricks under the floor boards, just numerous mouse holes.

 

[Penners]

You should certainly have some airbricks below the level of the suspended floor, to ensure that the void is well ventilated. Are you sure these don't already exist? The howling draught that you've described sounds more than a mere mousehole-worth!

Some insulation under your floor would probably help the temperature of the room. Lift the floorboards and tack some strong netting - polypropylene or similar - to the under side of the flooring joists. Stretch it good and tight.

Now lay insulation material the thickness of your flooring joists on top of the netting, so that it fills the voids between the joists, then relay your floorboards.

Make sure there is a good air gap remaining between the insulation material and the soil.

Fitted carpet will also be beneficial.

 

[billybob]

Hi

I'm begining to wonder if the howling gale is coming from an old chimney. Originally the living room was two rooms, both of which had fireplaces, is it possible that what was once blocked up has now become open to the elements again!? Perhaps it is time to check out the roof and see how bad the chimney pots are and if the hidden chimney is closed up.

I really can't see any airbricks, the bottom layer of granite stones appears to sit directly on the ground, some of them are 50cm long and 30cm tall. The cottage walls are approx. 75cm thick.

It's good advice on the floor front, I definitely think this is the next step, I think while the floor is up I'll move the radiators perhaps even replace them with some bigger ones. I'll work out the BTU's required and fit suitable rads, as the ones in the room are too small.

 

[Nemesis]

Even if the chimney isn't capped I think you might notice a hole in the wall?

Anyhow - blocked chimneys should have ventilation.

 

[Penners]

I'm not sure how a chimney could cause a draught under the floor - blocked up or not. The constructional hearth should be at floor level, not below - unless the floor level has been raised at some point, leaving the hearth below floor level.

But if you're going to take up the floor, you should be able to see whether or not this is the case.

 

[MdB]

I'm not sure how a chimney could cause a draught under the floor - blocked up or not.

A draft needs both an entry and an exit. The draft could be coming under the floor, through the floor boards and out through the chimney. Blocking the chimney (not recommended) could reduce the draft.

 

[Penners]

I'm not sure how a chimney could cause a draught under the floor - blocked up or not.

A draft needs both an entry and an exit. The draft could be coming under the floor, through the floor boards and out through the chimney. Blocking the chimney (not recommended) could reduce the draft.

But billybob appears to think that the chimney is the source of the draught - not the exit route.