locating source of smell in a room

[MassiveJim]

We moved in to current property in August last year and I have noticed that the lounge has a weird smell to it whenever the door is left shut and the heating was on.
I am just about to start decorating the room and removing the current flooring so though it was a good time to try and tackle this weird smell.

I went in there just now and the heat from the sun through the windows has caused the same smell.
Very very hard smell to place and describe, its kind of a dry/dusty/fusty smell and its quite strong when the door has been shut, but can't really notice it when the door is left open.

Room is now empty apart from a single chair.
one of the window sills has blown in the middle and is soft there, but if I smell that spot directly the smell doesn't appear to be coming from there.
The floor creaks really badly, it currently has an engineered oak floor down that is coming up and I'll find out whats underneath it.

I have had every floorboard up in the room above and there is nothing in the ceiling void. no smell in the room above either.


Could this window sill be causing the smell ?
if not where do I start ?

 

[sja360]

I suspect it'll be the flooring underneath. Any issues with losing water pressure in the heating system etc? Is there any chance of looking under the ground floor via a hatch or anything?

 

[throwaway4372]

sounds like damp smell
check behind/under furniture for mould
get the flooring up to look underneath
check the outside walls for damage where water might get in (in addition to window sill which obvs needs fixing asap)
get a humidity measuring gizmo

 

[MassiveJim]

I suspect it'll be the flooring underneath. Any issues with losing water pressure in the heating system etc? Is there any chance of looking under the ground floor via a hatch or anything?

Yes central heating has been losing a bit of pressure, and I know the pipework for one of the rads goes under the floor.
Had boiler serviced recently and the guy said their was no air pressure in the expansion vessel which can cause pressure loss on the water side.

The plan is for the floor to come up anyway, so that isn't going to cause me any headache at all.
The floor does creak quite badly which could mean it has warped over time maybe ?
No signs of mould anywhere.

I'll report back once the flooring is up.

I'll get this window sill sorted whilst I am doing this room, just got to work out how to remove it now.

 

[BigBoy]

Sound alike you have stagnant air in a hollow floor, make sure floor vents are clear to allow air flow. Engineered floor tends to seal the under structure causing air to stagnate you might want to invest in a hydrometer and check the moisture content of any wooden structures.

 

[BUDFORCE]

He who smelled it dealt it

 

[radderfire]

I am guessing dry or wet rot in wooden structures under the floor. Rot has an earthy smell. When the room heats up, it is heating the air underneath the floor, so the molecules released by the rot are vaporised more and rising up into the room.

 

[MassiveJim]

I am guessing dry or wet rot in wooden structures under the floor. Rot has an earthy smell. When the room heats up, it is heating the air underneath the floor, so the molecules released by the rot are vaporised more and rising up into the room.

Not entirely sure what the structure of the subfloor is yet, but I do know the room used to be a double garage, which if built correctly would have had a lower floor than the rest of the house, so I just need to find out what they used to bring the floor up to the same level as the rest of the house.

 

[neilw]

Is there a letterbox in the room?

 

[MassiveJim]

Is there a letterbox in the room?

It's not that kind of smell.

 

[Hilly]

put your nose closer to the smell.

 

[m andrew]

living room has seen lots of flange over the years.

 

[MassiveJim]

put your nose closer to the smell.

can't locate it, the whole room smells of it.
Well it did until i started removing the floor, now it just smells of plywood/chipboard.

I have pulled up the engineered oak flooring, under that was thin foil backed underlay.
under that is 3mm ply with an ungodly amount of staples in it.
under that is a (pretty much) floating tongue and groove chipboard floor (green boards), there are a handful of screws dotted here and there allowing a lot of movement (and the worst creaking floor I have ever encountered) they seem to be glued together but not all of the joints are over joists. also the radiator pipes are/were sandwiched behind the skirting board, between the bottom of the plasterboard and the floor. So whenever someone walks past the radiator it would be moving the pipes.

Signs of a previous leak at one end of the rad (but only on the chipboard)

I haven't pulled any chipboard up yet as it was past 10pm last night when I discovered the above so couldn't start getting powertools out to cut into the floor, will try and look tonight.

The source of the knackered window sill is probably due to: outside there is an arch shaped piece of trim above the window that is fastened to what looks like a mostly rotten timber lintel, and the trim easily pulls away from the wall.
Both windows can be pushed away from the wall at the top, which suggests that the timber has rotted through on both side and the screws no longer have anything to fasten in to.

I have rang the local window fitters to see if they can quote me for repair.

 

[MassiveJim]

Part of the floor taken up now


I can't see any sign of the pipes leaking under the floor, but they are twisted around each other like spaghetti with no clips in sight anywhere.

What should I do with this floor now to make it "right" whilst spending as little as possible (note if I need to spend I will)

The floor creaks REALLY badly, there has been no treatment of the original garage floor, there are some timber bearers laid across it then these 4x2s on top, there is movement between the concrete and timber bearers and the 4x2s each have a single nail into the bearers, the bearers get smaller as you go further into the room , and I can see a 4" square of plasterboard being used as a bearer under the floor further up. There are very few screws in the chipboard as well so there is a lot of movement between chipboard and the 4x2 which is probably where most of the noise is coming from.

I'm thinking the entire floor needs pulling up, but I don't know what to do to make this right.
Should I screed the floor level and then relay the 4x2s, if I do that do they need drilling into the concrete to secure them ?
Should I add insulation ? if so what thickness ?

 

[kindai]

Build a wall in the middle of the room, see if its coming from one side or the other. Never go in the bad smelling half again.

 

[BigBoy]

I'm thinking the entire floor needs pulling up, but I don't know what to do to make this right.
Should I screed the floor level and then relay the 4x2s, if I do that do they need drilling into the concrete to secure them ?
Should I add insulation ? if so what thickness ?

For the love of God rip that floor up get that radiator plumbed in and get it done properly, no wonder is noisy and smelly, probably damp plasterboard rotting away slowly causing the smell.
Engineered wood or laminate would have created a vapor lock under the floor boards. I'm fairly sure that's what is causing the smell.

 

[MassiveJim]

For the love of God rip that floor up get that radiator plumbed in and get it done properly, no wonder is noisy and smelly, probably damp plasterboard rotting away slowly causing the smell.
Engineered wood or laminate would have created a vapor lock under the floor boards. I'm fairly sure that's what is causing the smell.

There is no damage to plasterboard that I can see, so I have that one saving grace.

Having researched this a little since you posted, it has become clear that I need to sort this out properly.
Worth noting (and probably no surprise) that there was an indemnity policy taken out on this property for this room and the external garage by the previous owner.
From what I have read the indemnity policy covers me until I go and apply for retrospective building regs approval.
Should I apply for a cert whilst I am correcting this or is that just opening up a can of worms ?


Now the main question is how would you sort this floor out properly ?
having spoken to a mate who isn't a builder but has done plenty of work on his own house.
we came to the conclusion that easiest/best method here would probably be to level the floor of the old garage (hopefully just sand will be sufficient here)
then put down a DPM, then install celotex/kingspan to bring the floor up to the correct height, then a floating chipboard floor using glued tongue and groove chipboard(hopefully the chipboard that is already down can be reused)

Any thoughts are welcome, this isn't something I have dealt with before.

 

[Megahurtz400]

Probably not, but are behind the radiators/in between the fins clean?

I have electric radiators and turn them on so rarely that when I do all the dust inside them takes a while to burn off and it smells dusty and well, like burning dust....

 

[Mysterae_]

If you want to know if the smell is coming from your heating system add some of the smelliest perfume/aftershave you have (but don't use any more) to the heating circuit water. As it should be a sealed system you shouldn't ever smell it but if you do you'll be able to track it down easier.

Also, you haven't recently been divorced and taken the curtain poles with you? If so, check for frozen prawns .

I had a wool rug once that no matter how I cleaned it it still smelled like wet sheep, had to bin it.

 

[JayMax]

Could buy yourself a damp meter and go round the room to see if there is any damp.
Or air the room out, then close the door and go over it on your hands and knees inch by inch sniffing.