Window Trim Gaps From Cold Weather

[David Stone]

As the weather is getting colder, many of the window trims around my drafty old windows are separating at the joints and I'm getting cracked paint.  

I'm a bit surprised that the wood seems to be pulling along the grain - I thought temperature changes caused wood to move across the grain?  But not important.

I guess I should just spackel or caulk these gaps and repaint?

   

   

[jteneyck]

It looks like your house is in desperate need of a humidifier.  Those joints opened up because the wood is drying out from low relative humidity.  Once you get the RH back about at least 40% those cracks will close up again.  

John

[K. L. McReynolds]

That is also an indication of a shifting foundation. If the problem does not resolve with an increase in humidity, the cracks are semi permanent(fairly normal). Fill and paint.

[David Stone]

Thanks.  I'm hoping the foundation is stable -- the house is 100 years old.  But who knows.

We were in the market for humidifiers.  I guess I'll pick up the pace.

[EightFingers]

You probably have a rubble stone foundation. They move all the time and that causes cracks in the walls and trim.

[FS7]

That's not at all uncommon. Heck, with modern labor standards, you'll find homes that look like that on the day they're built. I would just caulk and paint.

[Snipe Hunter]

Thanks.  I'm hoping the foundation is stable -- the house is 100 years old.  But who knows.

We were in the market for humidifiers.  I guess I'll pick up the pace.

I'd pull off the casing and look behind it. My guess is there is zero to very little insulation behind it. You can get a non-intrusive look with a infrared thermometer by just checking the temp of the frame and casing vs the surrounding area of the wall. . If it were a humidity issue, you will see the problem all over the house, anywhere two pieces of molding are joined.

Houses settle so movement is to be expected. That doesn't look like foundation movement to me.

Are those single pane, non insulated glass windows? That will also cause it. You will have the most heat loss and thermal swings in non insulated areas... like at single pane/metal framed windows

I don't think lack of humidity is your problem. Just the opposite. If that area is significantly cooler than the rest of the wall, it will shrink more and you will get condensation concentrated in that cold area weakening the joints and causing even more movement in the wood/framing.

Heat was cheap 100 years ago, insulation wasn't.

You'll be chasing your tail caulking and painting. It didn't work for 100 years. It still won't work. Fixing the thermal defects will fix it. That might (will) mean replacing the window.

[jteneyck]

I'd pull off the casing and look behind it. My guess is there is zero to very little insulation behind it. You can get a non-intrusive look with a infrared thermometer by just checking the temp of the frame and casing vs the surrounding area of the wall. . If it were a humidity issue, you will see the problem all over the house, anywhere two pieces of molding are joined.

Houses settle so movement is to be expected. That doesn't look like foundation movement to me.

Are those single pane, non insulated glass windows? That will also cause it. You will have the most heat loss and thermal swings in non insulated areas... like at single pane/metal framed windows

I don't think lack of humidity is your problem. Just the opposite. If that area is significantly cooler than the rest of the wall, it will shrink more and you will get condensation concentrated in that cold area weakening the joints and causing even more movement in the wood/framing.

Heat was cheap 100 years ago, insulation wasn't.

You'll be chasing your tail caulking and painting. It didn't work for 100 years. It still won't work. Fixing the thermal defects will fix it. That might (will) mean replacing the window.

Valid points.  Single pane windows are huge thermal sinks and condensation often is a major problem.  Maybe that has weakened the frame and trim joints.  That other crack, however, does look like it could be related to settling, as someone else suggested.  Perhaps there is more than one issue involved.  

But I agree; it would be good to pull the molding and see what's back there.  Probably nothing.  I was more than a little surprised to see that the wall cavities of my house, built in 1961, had nothing more than 1" of fiberglass hanging in the 3-1/2" stud space.  Seriously?  

John

[Snipe Hunter]

That other crack, however, does look like it could be related to settling, as someone else suggested.  Perhaps there is more than one issue involved.  

If I saw the same over interior and exterior doorways and at intersecting wall joints, I would agree. But if it was only 1 window or multiple windows, I would assume thermal stress cracks.

[David Stone]

The second photo is just a layer of paint peeling.
 But I have these cracks in the corner of one wall.  I've dealt with these in the house I owned that had plaster walls.  I'm pretty sure is just the plaster reacting to changes in temp/humidity.

   

The foundation, at least what I can see in the basement is cinderblock. It seems pretty stable, except in one area (which will be for a later post).

The windows are original, old, single pane, and they lose a lot of heat. I use 1/4" backer rod to fill some gaps in the frame where the windows close (by cranks). We're considering replacing the windows, but it's a matter of cost.  And they're beautiful:

   

The prior owners priced out replacement windows, and they're expensive enough that it would takes many years of energy savings to make up for it. (Although we wouldn't have cold rooms.). Our neighbors replaced their windows and they said it will take almost 20 years of energy savings to pay for it.  

The walls were insulated sometime in the past, but of course I don't know the details. I know prior owners replaced all the wiring and interior plumbing.  I think they pretty much gutted. the place and did insulation, etc.  I'll find out in time.