How do I fix rotted portion of this bay window?


I am pretty sure the rot is from condensation in the winter. It goes all the way to the exterior though. I was going to try bondo to fill in the missing part. But when I saw it go beyond the window panes I wasn’t sure. Can this be fixed or is it time for a new window?

q how do i fix rotted portion of this bay window
q how do i fix rotted portion of this bay window
q how do i fix rotted portion of this bay window
  22 answers
  • Flipturn Flipturn on Oct 04, 2021

    Yes, it is time for a new window.

    Even if the hole was smaller and it was possible to patch up it up, this would be only a temporary 'fix' at best, as it would not address the reason why there is so much rotten wood, and how the water is getting in. Also, as the amount of rot showing is this extensive, there is likely more behind other parts of the window frame, the sill, and possibly even the the studs.

    Once all the damaged pieces are removed, it can then be determined what needs to be re-constructed again before the new window is installed.

    For anyone not familiar with what the framing looks like behind the drywall, here is a diagram.

  • Michelle Leslie Michelle Leslie on Oct 04, 2021

    Hi Luke, I think it's time for new windows.

  • Michelle Leslie Michelle Leslie on Oct 04, 2021

    Hi Luke, yes, it looks like time for new windows.

  • Michelle Michelle on Oct 04, 2021

    Yes a new window for sure! You are leaving your home open to termites and especially carpenter ants!

  • Yes, it's time for a new window, but you will also need to assess the wood structure around it. That water has been leaking below the window and probably causing the wood to rot.

  • Kathy Gunter Law Kathy Gunter Law on Oct 04, 2021

    It's hard to tell from the photo but a leaking window may be the source of your issues. If so, you definitely need it replaced. If the rot is in the frame only and your source is not the window, you can replace the frame and place the existing window back in place.

  • Sadly you’ll need new windows.

  • Yes, I agree, you need a new window.

  • William William on Oct 04, 2021

    More likely a new window. There may be hidden damage to the framing under the window. The damage can also attract termites. Call at least three window companies and see what they suggest. Inspection and estimates should be free. Bay window is expensive.

  • Seth Seth on Oct 04, 2021

    For all of the trouble you would go through to try and repair it, sometimes it's better to just bite the bullet and install a new unit. As others have said, you need to cure the problem that caused the rot. When you remove the old unit, it will give you the chance to properly assess the extent of any damage and determine the best plan to do repairs before replacing with a new unit. Find a qualified carpenter to give you an assessment of the damage and what your options are.

  • I would have the company come out and look at it that originally installed the bay window... or a bay window/window company. They may be able to fix it, or it may be best to get a new window... it looks like a seal may be broken.

  • Mogie Mogie on Oct 04, 2021

    Yeap time for new windows. I know they are expensive but right now if you are a customer to with the right power company they are offering a rebate of sorts.

    We got new windows about 6 months ago and already have seen a savings on our electric bill.

    But if new windows are not an option right now look into a product called Rock Hard Putty from lowes (and it is cheap also). Hubby used that stuff to repair some rotted wood on near the roof. The stuff is amazing and it takes paint very well just prime first.

  • Cheryl A Cheryl A on Oct 04, 2021

    you need to be sure there isn't a water leak or damage from water there and replacing the entire window is your best bet

  • Redcatcec Redcatcec on Oct 04, 2021

    Get several companies to come out and give demo's, get prices on a new window. Pick their brains and go for a high R value. They will have to repair the damage before they can do an install. Get a licensed and bonded company, with a warranty.

  • Betsy Betsy on Oct 04, 2021

    Hi Luke: Hate to be the bearer of bad news, but it looks like it's time for a new window. On the bright side, you may get a deduction on your taxes if you get it done this year :) Get several estimates, read the warranty/guaranty from each company carefully. When I got new windows, one said that they warranty the work only and if the product fails I would have to take it to the company. I'm in Michigan and they are in S. Carolina! Some don't guarantee that they won't stomp on your bushes and some want loads of money for a 2x4 to put in the frame. One even said that if they deliver the windows on a Friday and they are to install them on Saturday and they get stolen, it's on me! You also want a warranty/guarantee that is transferable. Check to see exactly what's covered and that it's in writing. A sales person can't change the contract, it MUST be part of the contract. And, you can barter the price, i.e., so and so can do it for whatever, what can you do? :) One company even told me that the base of the bay window was 1" thick oak. He showed me a sample and I was stunned that solid oak came in 7 plys! So, ask questions, get references, a start and finish date and what clean up is to be done and make sure they are insured, bonded and licensed. Check with the BBB for any issues. So, read the contracts carefully. Short answer - new window :)

    Good luck

  • Dee Dee on Oct 05, 2021

    Hi Luke; Betsy gave some solid information. I would also check with the neighborhood app "Next Door" for recommendations. Word of mouth means a lot.

  • Deb K Deb K on Oct 06, 2021

    Hi Luke, Here is a video that should help you do a repair on the rotted window, hope it works for you, it should at least buy you some time!

  • Em Em on Oct 07, 2021

    You can replace the wood not the window. If you cannot do it, go to a local Handyman site or Angies list to find someone in your area. Seal the new wood with a good primer and wood paint. Wipe up any condensation when you see it, don't let it puddle on sill. This looks like something else though. Water usually puddles at the bottom. If the wood is soft where the window sits replace the wood. Cheaper than a new window.

  • Homeroad Homeroad on Oct 08, 2021

    It looks like you have water damage. I would get a professional in to determine where the water is coming from . It could also be carpenter ants so best to get it looked at and then fixed.

  • Betsy Betsy on Oct 10, 2021

    Hi Luke: In reexamining your pictures, you just may have a roof leak or a leak on or in the soffit. That needs to be addressed before any further work is done. Water doesn't show up where the hole is, sometimes it meanders around until it finds a place to run out between some cracks. Go up into your attic and check the ceiling wood and see if you have any discolouration or darkening of the wood like a water stain or something. That may give you an idea of where the water is coming from.

    Good luck

  • Agnes Chrzanowska Agnes Chrzanowska on Oct 31, 2021

    its time for new wood board