Repairing wooden casement window putty

[Galen]

The management company for my block of flats has hired someone to patch and paint the wooden casement windows for the block of flats that I live in (at considerable expense). Instead of raking out the putty that looks to have seen better days, what they've done is simply added new putty to areas where it was completely missing (although they have actually missed a small area, which you can see in the bottom right of the second photo below).

I would have thought if any of the putty looked a bit past it it would have been better to just rake it all out and replace it instead of patch around it and leave it as a likely future weak point.

Is what they've done correct? Or would it have been better to remove and replace all of the cracked putty?

I've attached some pictures below from after the putty had been applied to try and show what I mean:

 

[Cubist]

I'm afraid the answer is Yes AND No. Others here may disagree with me but;

I would have thought if any of the putty looked a bit past it it would have been better to just rake it all out and replace it instead of patch around it and leave it as a likely future weak point.

Yes this is correct BUT - its not the best time of year to do this as its likely the timber of the frame, particularly the less massive components, will be swollen with water. Such work is best carried out during the summer months after the frame has had a chance to dry out and contract a little.

Is what they've done correct? Or would it have been better to remove and replace all of the cracked putty?

Given the time of year a temporary patch repair like this is acceptable provided that all loose putty was removed and replaced at the time. Personally I would have thumbed and rubbed some putty into the remaining cracks as this would aid later painting and help to prevent any further water penetration to the fames timber.

Frankly I think the drivers here are both consideration of the weather conditions as well as economy. It may be an idea to talk to the management company to understand whether they see this as a temporary but necessary short term repair pending full replacement perhaps next year or a more permanent fix.

 

[Galen]

Hi Cubist,

Thanks for your quick response.

To give you a bit of background which will hopefully answer the questions you've posted above, this is part of the regular scheduled maintenance for the property. The management company expect these repairs to last for 7/8 years (upon which they're budgeting to schedule these repairs again).

Without getting into too many details, these repairs are overdue and the management company appears to have rushed to get them scheduled in before year end. We went through the accounts at the AGM and there is absolutely no budget for these windows getting anymore attention until the next scheduled maintenance (in 7/8 years time), although that doesn't prevent me from repairing them using my own funds/time/energy.

I had thought that September/October is a bad time of year to be doing this sort of work (assuming the summer months would be best), but curiously I have seen some similar work going on nearby recently.

I guess the main takeaways are that in future this work should be conducted in the summer months, and any putty that looks to be on the way out should be completely raked out and replaced?

I don't have any more recent photos but I visited the flat this weekend and they had actually completely painted over the putty (which makes the cracks look slightly better, but really I don't think it's going to do much to improve the resilience of this old putty).

The survey I had done did mention "it is apparent that patch repairs to the windows have been implemented historically, though these have not been carried out to a particularly high standard." - it looks like if I'm still living here in 7 years time I'll need to be a lot more vocal about the timing and specification of these repairs.

 

[Cubist]

Window frames are probably the most likely visible manifestation of that painful phenomenon 'differential movement'. Cracks in the putty work and the paint at the right angle intersections of timbers are the direct result of differences in the rates of expansion and contraction of the materials and sadly I don't believe theres any viable long term solution that can be applied. Glazing putty, because it dries over time to a solid mass, will inevitably fail and will need to be totally replaced as to do otherwise risks the wooden frame rotting. Once cracks start to appear in the putty they can be repaired BUT like Arnie they will be back, and a lot sooner than one would like. Annual repairs will most likely be required and, to be fair, even new putty around the whole frame could begin to crack in less than a couple of years. Consequently I would suggest your management company needs to operate on the basis of an annual inspection and repair approach that includes the occasional replacement of all the putty for a given pane as needed.