Powdery beam - what would you do?

[Samantha L]

Hi folks. About 7 months ago we bought a Cotswold stone cottage which is around 200 years old. I did a thing and started picking at a loose patch of thick black gloss on a beam (bressumer?) and have scared myself and trying not to panic that the house is going to fall down

I found evidence of powdery wood which has been filled with pollyfilla then coated in gloss, probably exacerbating the problem. House is on an hill this room is an on the ground floor, a bit below ground level and is a bit damp, which is something we’re working on.

My question is what would you do with this beam? I’ve attached lots of pictures for reference. Thanks in advance.

 

[CroxyP]

If it’s structural it may be worth getting a structural engineer to look at it and figure whether you need to replace or methods of strengthening. I personally don’t think this is a diy job but others may have experience

 

[CroxyP]

If it’s structural it may be worth getting a structural engineer to look at it and figure whether you need to replace or methods of strengthening. I personally don’t think this is a diy job but others may have experience

 

[Cubist]

If I remember rightly yours is a stone built cottage and from the latest photos these timbers form the ceiling of a ground floor room and support a floor above for a bedroom in all likelihood. The photos also suggest that this damaged timber is directly connected and supported by another, heavier/larger, timber that also supports the ceiling and floor above. If I'm right that larger beam is the 'bressumer' that spans the entire width or length of the room while this damaged timber probably connects into one of the walls of the building. Also, that bressumer has previously been stripped of any paint and is now in its 'raw wood' condition.

Can you confirm the above please? Also, can you advise if there are any other exposed timbers in this room that also connect into that bressumer? And finally, what is the apparent condition of the bressumers wood where the other timbers connect into it?

With all due respect to @CroxyP; for now at least a structural engineers input would be a trifle premature and brings some risks - most of those boys will try to avoid invasive methods but when they do with timbers like that it tends to be with big pointy screwdrivers. For now, something more delicate is needed and with the aim of determining the probable final extent of the decay to that timber and whether any others nearby are also affected.

A further question for now; I'm assuming theres a wooden floor in the room above this one, have you detected any springiness or movement of the floor when walking across it? What kind of wood floor is it?

 

[Samantha L]

Hi both, thanks for the replies.

@Cubist, that’s correct, it’s a stone cottage. These are weavers cottages and may have been originally 2 x one up, one down as we are split level. The room above is actually the sitting room which spans the width of one half of the building. Two of the bedrooms were moved downstairs and the sitting room moved upstairs some time in the 80’s, presumably to take advantage of the views from the first floor. The beam or bressumer spans the width of the building (approx 5.5 metres), and sits on top of two large lintels above the windows in the two bedrooms on the ground floor.

Both bedrooms have two external walls, with the window walls, having had plaster removed at some point in time and are partially pointed with cement, which we have started to replace with lime. The huge lintels, which you can see a peek of from one of my pics are currently their natural state and quite soft in places. We have not attempted to do anything with them.

When we purchased the property we had a level 3 survey carried out. Surveyor noted the significant dip in the middle of the sitting room above with some springiness (all of which we raised as a concern prior to the survey) but said it was within tolerance, though could strap the bressumer it if wanted. He had no concerns, though obviously he wouldn't have seen with part of the paint removed. He didn’t comment on the lintels from memory. Not sure about the floorboards above as haven’t taken the carpet up yet. There is evidence of large sheets of boarding though as I can see the outline under the carpet in places.

 

[Cubist]

Thanks for the prompt reply.

The angles from which photos are taken can be deceptive and that ceiling rose light fitting is suggesting that beam is circa 120mm wide at best. Can you advise what the rough width and depth (from the lower face to the ceiling) please? Also, can you confirm that this damaged beam is circa 5 metres long and spans the full width between the external walls?

 

[Samantha L]

@Cubist have checked the floor plan and the beam runs 5.1m across width of building from one external wall to the other. The wall between rooms is a partition only. Got the tape measure out and the depth of the beam from ceiling is approx 120mm at the shallowest and width at narrowest point is 220mm.

 

[Kearn]

That’s quite the span for a relatively small cross section timber, without intermediate support. I wonder if originally there was a wall splitting the rooms and providing support from underneath.

Any SE will not like the dimensions and unsupported span, before we get into the decay and reduced thickness at the key point of deflection.

Personally, I’d be investing in some accros to support the beams. Then removing all of the crap to be able to fully assess the timbers.

You can see the original face, coated in linewash.
However, the condition of the timber doesn’t look great I’m afraid.
How far in will a screwdriver go when pushed at various points?

There’s nothing that can be done for timber that’s past it, in terms of hardness or any of that muck.

Stand underneath, have someone jump up and down and see how much movement you get in the centre. Video it level and horizontal and use a measure for some quantification.

 

[Cubist]

So presumably the partition wall that divides the two bedrooms also runs beneath this damaged beam somewhere near its midpoint? Hopefully, whoever did this work was wise enough to insert a post of some kind, and hide it in the partition, to provide some additional support for the beam. As a first move you should try to confirm or reject this hypothesis. It would be wisest to assume though that the partition wall has been constructed of a fairly light weight timber stud frame and, while this may afford some support for that bressumer, it may not withstand someone jumping up and down on the floor above - unless he's annoyed you recently.

Sadly some investigation with a long pointy instrument is called for though to determine how extensive the rot/decay problem may be. It's feasible that the decay you are seeing is restricted to an inch or less of the timbers depth - from any of its faces - and solid heartwood is swiftly encountered that resists any further efforts to penetrate it with a the screwdrivers head. You will need to test the timber at regular, say 30cm, intervals along its full length and at circa 7.5cm across the face and sides. You'll need someone with some 'elbow' to do this - a gentle touch is not appropriate.....and don't be afraid to push holes through that paint, that's the villain in this piece and some retribution is called for.

Come back to us when you done a preliminary survey or if you have any immediate concerns.

 

[LadyArowana]

I’m just here to suggest that a meat skewer may be less invasive, but provide same results, as a screwdriver when it comes to poking things into wooden beams.

 

[Samantha L]

Thanks all. I will get skewering and let you know how I get on!

 

[Samantha L]

Morning All. I’ve been round in both rooms along the beam with my veggie kebab skewer. At the very softest parts I can stick the skewer in 20mm. Some areas only about 5mm. Other half has done some conservative hopping overhead and whilst there is vibration, there no obvious bouncing from the beam. I’ve skewered the lintels while I was at it and they appear soft only up to 5mm depth.

 

[Cubist]

Thats very encouraging. Assuming the beam is/was circa 220mm by 220mm (120mm below the ceiling pus 100mm hidden) that would imply circa 180mm square of good timber remains. That mass should quite happily support quite large loads provided that the span is reasonable. Have you determined whether there is a supporting post beneath the intersection of the dividing partition wall and this beam? Glad to hear the other half didn't come through the floor with his 'judicious hopping about' earlier, that too is encouraging.

As suggested earlier the paint used on that beam is largely responsible for the damage you have found this far. Left in place this will continue to destroy those and perhaps also any others to which this beam is connected. You will need to remove the paint and any loose and desiccated wood to reveal the underlying good timber. Hopefully, this will confirm your 'skewer findings' concerning the timbers condition and you can then focus on measures to protect and preserve it.

 

[Samantha L]

Thats very encouraging. Assuming the beam is/was circa 220mm by 220mm (120mm below the ceiling pus 100mm hidden) that would imply circa 180mm square of good timber remains. That mass should quite happily support quite large loads provided that the span is reasonable. Have you determined whether there is a supporting post beneath the intersection of the dividing partition wall and this beam? Glad to hear the other half didn't come through the floor with his 'judicious hopping about' earlier, that too is encouraging.

As suggested earlier the paint used on that beam is largely responsible for the damage you have found this far. Left in place this will continue to destroy those and perhaps also any others to which this beam is connected. You will need to remove the paint and any loose and desiccated wood to reveal the underlying good timber. Hopefully, this will confirm your 'skewer findings' concerning the timbers condition and you can then focus on measures to protect and preserve it.

Thanks @Cubist, that’s reassuring. I haven’t determined the presence of any support in the partition yet. If there’s anything there I think it will be on the lighter side. The partition is very thin.

Will start on getting this gloss off. I think with the powdery softwood, hopefully not to difficult a job. What would you recommend to protect it going forward?

 

[Kearn]

Thanks @Cubist, that’s reassuring. I haven’t determined the presence of any support in the partition yet. If there’s anything there I think it will be on the lighter side. The partition is very thin.

Will start on getting this gloss off. I think with the powdery softwood, hopefully not to difficult a job. What would you recommend to protect it going forward?

Absolutely nothing is required, as there’s nothing it really needs protecting from once free and able to dry out.

I’d be inclined to scrub off the loose bits, vacuum first then maybe a light brushing with a churn brush to remove anything loose, but don’t go too far. Then liberal coatings of limewash as it once was. This will help consolidate the loose timber, fill holes and gaps and give a less scrappy finish as I doubt much of the surface is left intact, so the appearance will certainly be ‘rustic’.

 

[Samantha L]

Absolutely nothing is required, as there’s nothing it really needs protecting from once free and able to dry out.

I’d be inclined to scrub off the loose bits, vacuum first then maybe a light brushing with a churn brush to remove anything loose, but don’t go too far. Then liberal coatings of limewash as it once was. This will help consolidate the loose timber, fill holes and gaps and give a less scrappy finish as I doubt much of the surface is left intact, so the appearance will certainly be ‘rustic’.

Ok great, rustic is fine by me. The external wall with the window is about to be limewashed after having cement pointing removed and we’ve bag rubbed with lime, so I’ll do the beam and the lintel too.

 

[Samantha L]

Thanks for the advice everyone. I’m feeling reassured, especially I now have a plan in place.

 

[Cubist]

Good luck and enjoy the old place.

 

[Mulder]

I'm late to this thread but thought I'd add my comments incase it helps.

You say the beam spans the whole room and is supported on a pair of lintels. This is almost exactly the same as our house, similar age and purpose by the sounds of it too. We have two of them infact in both downstairs rooms (also a two up, two down).
Our beams were a much later addition. I think one of them hides a metal tie bar. I assume they were installed when the original upstairs floor joists started to bounce a bit too much, or maybe the original beam didn't make it. Our heritage surveyor said how unusual it was to have such a beam above window lintels and suggested this was a clue it was not the original design.

Like you, ours was also covered in the same black paint which disguised a lot of cement repairs. We had ours 'blasted' and the results were not as aesthetically pleasing as we had hoped; lots of rot and wood worm. However, they do seem much better now they're out in the air so I would advise you to consider getting the paint removed. You can probably do 90% with chemical peel products but it will still be messy.

Good luck