Chipped paint and cracked wood on window. SAM Conveyancing's guide on handling a rotten window frame
Spotted a rotten window frame in a house you're buying?
A house survey will reveal how serious the problem is and whether or not you should be worried.

We offer same week availability, our fees are fixed and we'll make access arrangements, so you don't have to.
Get a Survey Quote

Rotten Window Frame

(Last Updated: 12/12/2023)
5 min read
Key Takeaways
  • A rotten wooden frame shouldn't cause too many problems if spotted early. Signs of rot are easy to see, but if you're buying a property, your house survey should uncover this.
  • If you already own the property, there are ways in which you can maintain your wooden frames, so you avoid the development of rot.
  • Once you're aware that your window frames are rotten, you can take the necessary steps to fix this. You can either treat the affected area or replace the frame altogether.
  • Rotten window frames will be picked up in your level 2 or level 3 survey.

Why is window frame rotting?

In most cases, your window frame will start rotting because it is exposed to damp. Cracked or peeling paint will allow the water to seep in. The wood will then absorb it and this will lead to rot. The longer the wood is exposed to these conditions and the longer it is left untreated, the more serious your problem will become.

If the wood frame is really old, any cracks will make it more susceptible to moisture and damp. Regular maintenance will ensure that you don't have to worry about a rotten window frame.

How to keep wood windows from rotting

You can keep your wood windows from rotting by painting them with a waterproof wood sealer. This will stop moisture from being able to penetrate any cracks in the wooden frame.

Similarly, if you notice any cracks in the frame, you can easily fix it yourself before it turns into a more serious problem. We explain the process below.

What does window rot look like?

  • peeling paint or a wavy, bubbly aspect to it
  • cracks in the wooden frame
  • crumbling wood sections
  • fungal growth on the wood
Rotten Window Frame   Rotten Window Frame
If you're buying using a mortgage, your lender will carry out a valuation of the property. Any signs of damp, which could cause your wooden frames to rot will be identified during this process. Your mortgage lender might make it a condition for you to get a Damp and Timber Survey on the property.

How do you fix a rotten window frame?

There are various treatment options for a rotten window frame. We discuss them in more detail in our article - Dry and Wet Rot Treatment.


    Identify the extent of the problem

    If the rot has extended on more than 10% of the window frame, you might be forced to replace the affected section or the entire frame.

    Remove the affected area

    Thoroughly removing the rotted section will ensure the problem doesn't spread. This should be an easy task, as rotted wood will be softened and easy to remove.

    Fill in the gaps

    You can restore the frame to its original state by using wood fillers. This will fill all the cracks and create a stronger barrier. You can easily purchase what you need for this project.

    Sand and make the surface smooth again

    You should first focus on sealing all the cracks with the wood filler. You can then sand the entire surface down, to prep before painting.


    Make sure you use multiple waterproof wood sealer coats, to prevent the wood frames from getting rotten again.
If you spot a rotten window frame in the early stages of it developing, you might be able to reverse it by using a wood treatment.

Can you replace rotted window frame?

If you (or the surveyors if you're looking to buy a house) find that the damage is too great to attempt repairs at all, you can always replace the rotten window frame. You do not have the replace all the windows inside your property, only the affected ones. Similarly, you can either replace the entire frame or just the parts that are affected.

If you're buying a house, it is necessary for you to check for any signs of rot in the wooden frames, as this could turn out to be an extra cost for you. Both your level 2 and level 3 surveys will attempt opening all the windows, if possible and given permission. Your solicitor can then help you negotiate with the seller to have the windows repaired before sale, or they may be willing to reduce the purchase price to reflect the cost of you repairing them yourself.

16% of homeowners discover defects

In our recent survey, 16% of homeowners found defects; including 2% who were able to pull out of a bad purchase, 7% who were able to negotiate a better price, and sadly, 7% of homeowners who did not get a survey and discovered defects after the purchase.

12 of the 39 who remembered how much these defects cost to remedy spent over £5,000

Don't burn your money, book a survey.

RICS Surveyors | Fixed Fees | Same week availability | Access arranged

Frequently Asked Questions
Laura Cristian - Digital Marketing Assistant - Meet the team - SAM Conveyancing
Written by:
Laura has a talent for data analysis and fact-finding. She is an advertising graduate with a broad range of skills in the web marketing field within conveyancing sector. She works closely with our panel of solicitors and surveyors to understand our clients' needs and challenges and to write the most valuable content for you.
Andrew Boast of Sam Conveyancing
Reviewed by:
Andrew started his career in 2000 working within conveyancing solicitor firms and grew hands on knowledge of a wide variety of conveyancing challenges and solutions. After helping in excess of 50,000 clients in his career, he uses all this experience within his article writing for SAM, mainstream media and his self published book How to Buy a House Without Killing Anyone.

People also searched for

Property Survey Defects explained by SAM Conveyancing

Property Survey Defects

A guide on Dry and Wet Rot Treatment from SAM Conveyancing

Dry and Wet Rot Treatment

No FENSA Certificate for Windows or Doors for Double Glazing

No Fensa Certificate for Windows