Damaged Window Sills

Damaged Window Sills

Damaged window sills, on wood construction windows, are one of the more common repairs we are contacted about.  Because window sills present a somewhat flat profile and have multiple joints where the brick molding and sash tracks terminate, they are susceptible to decay.   Damaged window sills, that remain unrepaired, can lead to other more extensive damage to the structure, including decay of the exterior siding, wall framing, hardwood flooring, sub-flooring, floor framing, as well as stained and moldy drywall.  Ants and termites may also be attracted to, and subsequently infest areas that are persistently damp.

Damaged Window Sill

Window sills with only minor damaged may be repaired by replacing  just the sill nosing or by removing the damaged area of wood and using a filler, such as bondo body filler, to repair the damaged area.  Review the  post “Woodpecker Damage Repair” for detailed instructions on how to make a repair using body filler and view the slide show “Chimney and Window Sill Repair Project” to see a window sill repair project utilizing body filler.

Severely damaged window sills render the entire window unit unfit for use.  Proper repairs are achieved by removing the interior window trim and then the window unit, including the exterior trim or brick molding.  Any damaged siding should be removed at this time.  If the wall framing under the window shows signs of damage, additional siding as well as drywall from the interior, may have to be removed to facilitate repairs to the framing.  Once any needed framing repairs are completed and the rough opening is properly flashed, a new window unit can be installed. The exterior repairs are then completed by installing any required siding, then caulking and painting the window and surrounding siding.  Interior repairs are completed by replacing any insulation and drywall that were removed and installing the window trim.

Some window manufacturers have begun to use composite window sills and sill nosing along with vinyl brick molding which greatly increases the weather resistance of windows utilizing those components.  WHMS encourages the use of windows featuring these weather resistant components whenever feasible.


Did you enjoy this post?  Tell us what you think in the comments box below. 


Want to see more?
Subscribe to our RSS feed  or Subscribe by e-mail

Wood’s Home Maintenance Service offers solutions for a wide range of building, maintenance and repair needs.  Give us a call or click the button below to contact us  today for a free estimate.

Contact us about damaged window sills

About Tony Wood

Tony is a life time resident of North Carolina with over 40 years experience in multiple facets of the industrial, commercial and residential construction industry. For the past 33 years he has owned and operated Wood's Home Maintenance Service, providing services primarily in Johnston, Wake and Sampson Counties of North Carolina. ______________ ______________________________________________________ The information contained in this Blog is opinion derived, from hands on experience of over 40 years in the construction industry and by extensive research by the author. All postulations are referenced to the geographic location in which this experience was gained.
This entry was posted in Exterior Maintenance. Bookmark the permalink.

Leave a Reply

Your email address will not be published. Required fields are marked *