Condensation after woodburner installation.

[amfisted]

Hi All

Problem with condensation; sorry, not strictly a plumbing or central heating question.

We recently had a multi fuel stove fitted in our lounge to replace a coal effect gas fire; partly for long term fuel savings, partly for reasons of sustainability, and partly because we had hoped it would allow us to heat the cold, flat roofed front garage conversion bedroom in our bungalow. I intended to do this by leaving the door open from lounge to bedroom when the stove was on. Instead, it seems to have created an unexpected problem.

I have the stove burning tonight and I've open the door to the porch, which leads to the front bedroom, to allow the stove to heat both rooms. When I went into the bedroom to check the temperature I found that all cold surfaces, mainly walls and window but also wardrobe doors, were streaming with condensation. So much so that the matt paint finish on two of the walls appears to be developing a patchiness. The room is normally unheated when not occupied, and although it gets cold because of the uninsulated flat roof and we've noticed a mouldy smell in one of the wardrobes after the end of winter there's never been anything to this extent.

Could it be that some of our firewood is damp and that damp is transferring itself to the atmosphere and then finding its way to the walls of colder rooms? Any other possible reasons why we might have this issue since installation of the woodburner? I could apply anti condensation paint to the bedroom walls, but that would be sure to transfer the problem elsewhere.

Thanks in advance.

 

[Lower]

Was there much work done to fit the new fire? Lots of plastering or rendering?

Lots of water comes out as it dries.

 

[amfisted]

The fireplace had to be doubled in size and there's a square metre or so of drying plaster around the edges. To me, the amount of condensation currently evident seems way out of proportion to the extent of that area, but I'll let it dry and see whether the situation resolves itself.
If not, I'm stumped.

 

[ajstoneservices]

Did you have a CO alarm fitted at the same time as the stove ? If not get one now.

 

[FiremanT]

Aj,(and OP), the question of spillage (of fumes), which causes condensation, occurred to me yesterday when I first read this, I would have assumed that if the SF fire is spilling, smoke or smell should be evident, but,frankly, I don't have enough experience of solid fuel to be sure. Regardless, CO alarms are inexpensive, so, OP, have at least one in the room with the fire, and I would have one in the room where the condensation is evident, at least temporarily.
Is the garage conversion attached to next door?
Is the flue lined?

 

[motorbiking]

The surfaces of your uninsulated room are cold, the hot air from your fire is warm. This causes condensation. You'll either need to install a dehumidifier, increase the temperature in the uninsulated room or properly insulate the room.

 

[ajstoneservices]

Once we know it's not a CO problem then you can look elsewhere.

 

[amfisted]

Once we know it's not a CO problem then you can look elsewhere.

Definitely not a CO problem. We have a brand new detector and there's no evidence of any leakage.

 

[amfisted]

The surfaces of your uninsulated room are cold, the hot air from your fire is warm. This causes condensation. You'll either need to install a dehumidifier, increase the temperature in the uninsulated room or properly insulate the room.

Thanks for that.

My intention was to use the woodburner to raise the temperature in both lounge and front bedroom so that conditions were no longer conducive to condensation of water vapour on the cold bedroom walls.

To properly insulate the room would cost too much, so I guess my dream of heating two rooms for the price of one is literally out of the window.

I do have a dehumdifier, so I guess I could try running that whilst the door to the cold room is open, and see whether it cures the problem.

 

[amfisted]

Aj,(and OP), the question of spillage (of fumes), which causes condensation, occurred to me yesterday when I first read this, I would have assumed that if the SF fire is spilling, smoke or smell should be evident, but,frankly, I don't have enough experience of solid fuel to be sure. Regardless, CO alarms are inexpensive, so, OP, have at least one in the room with the fire, and I would have one in the room where the condensation is evident, at least temporarily.
Is the garage conversion attached to next door?
Is the flue lined?

The property is detached and the cold bedroom /garage conversion has three outside walls. All cavity.

And yes, the flue has been lined, and the stove was fitted by a HETAS qualified engineer. CO alarms are present as stated above, and in both rooms. I'll experiment using the dehumidifier whilst the stove is burning and the door to the bedroom is open.

 

[Doggit]

Would I be right in thinking you have your windows closed to keep out the draughts, and keep in the heat. If this is the case, then the warm air from the stove is moving the excess moisture in the house into the cold rooms. Run the dehumidifier, but also try opening the windows for a few days with the stove going, and see if the problem goes, then turn off the dehumidifier, and then see how things are. Most people don't realise how much moisture modern day living puts into the air, and it's got to settle out at some point.

 

[Dan Robinson]

Definitely not a CO problem. We have a brand new detector and there's no evidence of any leakage.

Is that a professional, insurance backed opinion... Or a "I've bought this from a retired duffer at BnPoo so it must be right" opinion?

How many gas/combustion engineers use over the shelf alarms for their day to day safety? Oh.... Wait.....

 

[amfisted]

Is that a professional, insurance backed opinion... Or a "I've bought this from a retired duffer at BnPoo so it must be right" opinion?

How many gas/combustion engineers use over the shelf alarms for their day to day safety? Oh.... Wait.....

Confession time: we had quotes from three HETAS engineers and the one who gave the cheapest quote got the job.

I've had several good local recommendations for the same chap so I'm not concerned about the quality of his work. However, on first visit he did say he would fit a CO alarm to the ceiling within, I think 3m of the fire, as part of the installation.

Coincidentally and following problems with the CO emissions of a now departed gas fire which are also mentioned on this forum, I'd bought a brand new, 7 year, sealed battery CO alarm just a few weeks before the stove was fitted. He didn't supply one because presumably he thought two CO alarms in one room was overkill, and I didn't query it.

However, if you think he should give me a new CO alarm anyhow, given that it was supposed to be part of the contract, I'll call him up and ask for it. He's a decent chap and I don't think he'll quibble. After all, he did discover that our chimney pot wasn't fit for anything but the bin once he got on the roof and examined it, but he only charged for the cost of supplying a new pot and not for fitting, even though he was up there for an hour at least.

 

[amfisted]

Would I be right in thinking you have your windows closed to keep out the draughts, and keep in the heat. If this is the case, then the warm air from the stove is moving the excess moisture in the house into the cold rooms. Run the dehumidifier, but also try opening the windows for a few days with the stove going, and see if the problem goes, then turn off the dehumidifier, and then see how things are. Most people don't realise how much moisture modern day living puts into the air, and it's got to settle out at some point.

Yes, you're absolutely right. I know that sealed rooms and houses are the perfect breeding ground for condensation and mould, but apart from opening our bedroom window at night and nervously cracking the back door open for a split second every half an hour or so before booting our elderly dog out into the cold for a wee then slamming the door shut on the poor old bugger, we're all tightened up against the cold most days. However, I'll give your suggestion a go and see what transpires, thanks.