How to Replace a Rotted Windowsill | This Old House

This Old House general contractor Tom Silva shares some tricks-of-the-trade for installing a new, long-lasting windowsill. (See below for tools and a shopping list.)
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Tools for How to Replace a Window Sill:
- Oscillating tool [amzn.to/2Xf1Tew]
- Reciprocating saw [amzn.to/2Wd7R35]
- Flat pry bar [amzn.to/2Wj21gZ]
- Hammer [amzn.to/2EFmwcR] and 3/4-inch-wide chisel [amzn.to/30S4ddE]
- End nippers [amzn.to/2wuUv2U]
- Circular saw [amzn.to/2XeIsCy]
- Layout square [amzn.to/2JM9mPo]
- Drill/driver [amzn.to/2Xb40A1]
- Handsaw [amzn.to/2Quq5qX]
- Hand plane [amzn.to/2WDRzA1]
- Random-orbit sander [amzn.to/2QzsFf7]
- Caulk gun [amzn.to/2K92x9O]
- Dead-blow mallet [amzn.to/2KdSiRQ]
- Pneumatic finishing nailer [amzn.to/2KcXdlM]
Shopping list for How to Replace a Window Sill:
- Spanish cedar [amzn.to/2Wema7K], used to make new sill
- 3-inch screws [amzn.to/2Kf6euD], for pulling out old sill
- 120-grit sandpaper [amzn.to/2MgQU3a]
- Spray primer [amzn.to/2K96LhG], for coating new sill
- Silicone caulk [amzn.to/2wqGJyx], used to seal new sill into place
- 2-inch finish nails [amzn.to/30Qhzaq] for pneumatic nailer
- Minimal-expansion foam [amzn.to/2I5sBA6], for filling void below sill
- Exterior-grade paint [amzn.to/2WdEygR], to match existing window trim
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How to Replace a Rotted Windowsill | This Old House
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[@MrKelly-ll1lx]

The screws to help the prying was on point!🔨

[@bcask61]

Tommy Silva is the MAN. I have been in the trade for 35 years and I still learn things from him.

[@trevorhawkins8757]

Me and my dad replaced four of these windowsills on our second floor in one weekend. Contractor told us entire windows and surrounding structure needed replaced. Saved me over 5 thousand dollars.

[@hawklerfalco9067]

Yeah, right way.

[@CheeseBae]

Contractors are going to tell you what will be the least amount of work for them with the maximum amount of profit.

[@trevorhawkins8757]

@@hawklerfalco9067 right way? Took back the siding and vapor barrier and everything surrounding the window was in perfect condition, not wet or any rot. Why would I replace it all when one piece of wood needed replaced bc previous owner forgot to caulk around the bottom?

[@r1g8p7]

That’s what sucks. You always have that doubt because a lot of these contractors just can’t be honest.

[@ajs96350]

@@CheeseBae "Some" contractors, not all.

[@SelectBlinds]

A video that shows you four tips in about 15 seconds...pure GOLD! This is excellent!

[@tomasvanschaik5749]

I have a project to replace the window sills on a tired old church. Of all the KZbin vids I have seen “and many were very good” this one has been the best.

[@outdoorguy845]

He took three measurements and then walked over and started making cuts. Didn't even write anything down or draw a diagram. When I take a measurement, I walk over to the piece of wood and I already forgot what the hell the measurement was.

[@boonang4097]

Master Carpenter Builder Tom truly likes what he does. So taking and remembering measurements is easy because he had his heart in what he does!

[@michaelcarroll991]

No he did. They just didn't show it.

[@leehancock2782]

These guys are badass

[@MarkOhanesian]

I write my measurements down and still make the cut wrong the first time

[@drumsnbassisALLIPLAY]

I not only forget the measurements from the first time I measured-I forget that and I then I cut it wrong. Then, the second time it’s pretty close and it’ll do. Caulk and paint can make me the carpenter I ain’t.

[@erictold]

This video saved me. I replaced two sills today. I used pre-made PVC sills from big box stores. Removing the sills were tricky but with this video, I could remove them in minutes.

[@buzoff4642]

Lucky you! I'm not seeing pre-made pvc sills that come anywhere near the thickness the one they removed.

[@keithrayeski3147]

Another great video. AND, what I enjoyed the most, was the home owner right there not just watching, but DOING so HE can learn how to take care of his own home himself! Two thumbs up to Tom for being not just a doer, but a teacher!!!

[@peterpowers4851]

Tom is such a boss that he didn't even need to test fit it before he layed the bead of caulk because he knew there was no way that it wouldn't fit.

[@speedracer2336]

Been watching TOH over 30 years, never gets old!

[@SkillBuilder]

What a perfect video, well shot, well explained and easy to follow. Thank you.

[@marksuper4920]

I was able to replace a window sill following this video- thanks so much for making it simple and easy to follow!

[@jethronh]

i need to do this soon. i have 1870 old house with a back window sill thats rotting. This video will be a perfect guide. Thanks.

[@Coronet_1969_]

Tom is a master carpenter...so impressive with all the little tips he gives but his array of tools surpasses what I have by twenty-fold at least.

[@jhi1947]

Tom Silva is the man!

[@1bishw]

Looks pretty straightforward, until you have to do it from a ladder on a second story window.

[@JohnDoe-pt8vt]

Rent and build a scaffolding

[@lostintime8651]

I make a list of the things I need to get done high up on my house. Then when I take some time off from work I rent a man lift. Then I attack the projects on the list. 2 years ago I scraped and painted all the trim high up, repaired a chimney and fixed my slate roof. It was about $700 for 3-day rental of the man left. I had an estimate for $2,500 to repair the chimney. I saved a lot by doing this stuff myself.

[@lostintime8651]

@@JohnDoe-pt8vt a man left is easier to rent and set up and use. And much safer than scaffolding.

[@GDanielCho]

at 2:58 the slap of tom silva is deadly lol

[@rbeck3200tb40]

Wood is scared of Tom Silva

[@kojimasan444]

LMFAOooooo

[@mikeblank7165]

Watching this video, half way thru, and I am already exhausted !

[@kalijasin]

Tom Silva Is a Master Craftsman.

[@jpulley]

the best video on youtube on sill replacement.

[@braedenbrown6691]

I Totally Agree With You. Most of them video in Low Light or You Cant See What They’re Doing!

[@larrysouza581]

You my man are the best amazing work Tom and with great knowledge comes great responsibility .

[@robertsheppard5623]

Always has the right tool and the proper piece of wood always helps.Color me jealous. Great job.

[@davidmontgomery9968]

A great explanation. You have to respect such a competent craftsman.

[@boonang4097]

Tom. Amazing Crafstman! Thank you for sharing the video. Awesome. 👏

[@andrewsanderson2591]

Niki T - in England,it's called a "drip groove"; a groove made underneath a sill to make water drip from it,rather than continue back towards the house.

[@MrKelly-ll1lx]

That groove idea was something I didn't know!

[@BrianPhillipsRC]

you make it look so easy!

[@DoyleHargraves]

Mr. Silva, you are a damn good carpenter. I thank God for good craftsmen, like yourself, who are happy to help and teach. Thanks!

[@MeiinUK]

A beautiful job. Well done !

[@MrPolanka64]

The old man is incredible

[@richardorsulich4698]

Awesome, this is exactly the job I have to do on my house

[@marcelomerchan9563]

Thank you so much. You are a great teacher !

[@stonelark]

These videos are incredibly useful for homeowners who like to do their own handyman work. Thanks!

[@lathamarea1437]

Tom is very knowledgeable..I liked Norm as well...

[@macoy321]

He makes it look so easy

[@kalijasin]

Second nature for Tom Silva. 🙊

[@san379]

great job..love old windows instead of changing it out for vinyl

[@axg275]

Thank you so much this video really helped me!

[@Novagunner]

Great replacement Video, one critique i would suggest priming all raw with a oil primer, before laying your sealant. Where i live Water rot is due to the capillary water action that will exist in all wood causing expansion and contraction of the wood (as im sure you know) Using a good oil primer to seal the capillaries(and the surface) will insure the piece NEVER rots.

[@ryane6719]

Oil for sure. We use fine paints of Europe oil based undercoater on all six sides of any boards when doing restoration.

[@sbennet1447]

​@@ryane6719 What, specifically, do you use ?

[@ryane6719]

@@sbennet1447 exactly what I said is what we use lol.

[@TheNewsHoundLtd]

Thanks - this was really useful for a project I'm currently working on.

[@johnjvaughn]

thank you, couple of great tricks in there with the screws for removal an the spray foam.

[@powhoundus]

They make insect proof foam - what I would use around exterior windows because carpenter ants loved my windows and surrounding wood! And of course low expansion on the sides.

[@billynolanjr2266]

I love this kind of work, just enjoy doing it !

[@ItchyKneeSon]

I'm currently doing a sill replacement on a pair of side-by-side windows on a house built in 1946 in Ohio. The sill is rotted because someone thought it was a good idea to fully caulk the weep holes on the storm windows. 2 of the 4 counter weights' ropes broke, so the weights are sitting where the sill needs to go which is blocking me from sliding the new sill in. I'll be making a piece of wood to force them up and out of the way so I can slide the sill in. Like most things, this is proving to be much more work than expected. This video has been a great help.

[@barryclarke3010]

excellent job a pleasure to watch, professional guy , i do this type of work now and again being a carpenter, this guy is laid back and professional in his approach witch shows years of experience.

[@paulcook7986]

A great guide for a guy to follow, thanks.

[@Fundywhatshappening]

You are so helpful!! Needed this for this weekends project

[@hawklerfalco9067]

Oh my, right is what I need now, thank you so much the clear video!

[@RyneOller]

It's disgusting how easy he made that look.

[@kirkedelen3716]

He is really good! Great to see American craftsmen at work

[@larryschlais2143]

Looks like a very light stand and portable very well done

[@jeffreybaba4155]

You make everything look easy Tom😊

[@Jin420]

PERFECT TIMING! 😊😊 I need to start back on working the exterior of my house again. (Windows being one of the projects) Beautiful house which had been horribly neglected for decades. I'm in the process of trying to revive it. 😊 1931 Victorian style ...

[@nhanhuynh4761]

Mr Dblock .. this man very skill... his profesdional work... hihihi... Đây là cao thủ võ lâm trong ngành xây dựng

[@markbonham3477]

Just what I needed, thanks

[@carlosolivera4331]

Damn this guy is good. I am always amazed

[@williamb454]

Nice work!

[@jaysonburns4423]

I want this guy working on my house he know his stuff I've seen lots of his work

[@tydang3582]

A true master.

[@Smudgecat1947]

Excellent work - thank you! :)

[@jjb1974]

Very informative. Thank you!

[@GalaxyDesign100]

Thanks for the great video.

[@squidlings]

Brilliant. Some great tips

[@Gman6755]

Tom is the man!!

[@loktom4068]

Good tutorial and good job. Bravo.

[@cwilliams9891]

Great tutorial

[@markbailey3650]

He is a God!

[@steventhechef1538]

Great video. Thanks for posting

[@christobar]

I unfortunately have several sills that are in bad condition. I'm sure I'll be watching this video several times to get the steps right :)

[@abcomatic]

@James Draper III You've posted this link how many times now??? Time to cool it, ya think??

[@stupidass4567able]

Me as well. Rotted to dust basically

[@ChrisSilverman]

after 1 window you'll be a pro for sure.

[@AStanton1966]

For anyone else, I would recommend starting with the windows people see the lest of. Then progressive to the prominent windows.

[@brittneyrose7272]

That was extreamly helpful

[@kristinadoyle1313]

Thank you so much for this video

[@hectorcorral2419]

got to say that saw you have is one of the best tool i ever used i got 3 of the porter cable saw boss 345 the video was also great

[@lesbolstad]

That sill cut is pretty common and available at most home supply stores; and they come primed as well. Much easier and less expensive option.

[@OldRaver]

Thanks Robert :)

[@mattimus8250]

Thanks Tom.

[@mr_goodbear]

This guy is a magician.

[@bee.p.jr.4062]

Very useful information...

[@boejiden.1445]

wow. excelent job

[@tradedossier]

Thank you!

[@swizzleproxi4810]

That was a lovely job to watch 😍👌

[@michaelfuller2153]

I enjoy watching these...Tom has a plethora of building techniques! Now I'll go look up plethora. 😊

[@nicksoapdish9478]

Jefe, would you say I have a plethora of piñatas?

[@michaelfuller2153]

@@nicksoapdish9478 I dunno...I never looked it up! No soy el Jefe...I'm just a little Indian! 😁

[@nicksoapdish9478]

@@michaelfuller2153 I would not like to think that someone would tell someone else he has a plethora, and then find out that that person has no idea what it means to have a plethora. 😝

[@angkit216]

Thank you.

[@andreina818]

You sir are my new fave KZbinr

[@J_Lag]

"good for the next 50 years" and I do believe him lol.

[@machin9267]

Third world houses are better, and last for hundreds of years 🤣🤣🤣🤣 we don't live in rotten houses

[@g.pblack507]

@@machin9267 this statement makes no sense all buildings need maintenance and wood rots no matter what country your in

[@favioescalon528]

@@g.pblack507 the thing is that a lot of house in the 3rd world are not made of wood, they're made of bricks. I'm from Honduras and we were middle class. The house was very nice and I'm telling you is going to last a long time because they're not made of wood. Homes can be made of bricks because they have no insulation.

[@g.pblack507]

@@favioescalon528 I'm not desputing that. I'm saying that all buildings including brick and metal need to be maintained. Just because the house has some rot doesn't make it a bad building.

[@g.pblack507]

@@favioescalon528 also brick buildings will eventually need to be repointed as brick joints crack and fail.

[@buddhistjohn]

Thanks

[@pcm7315]

Made it look easy - I couldn't even remember the measurements.

[@writethisthat3613]

Yep. Same here.

[@gpslightlock1422]

150 Years. Tom Silva did it!

[@tarynsanmartino8930]

Tommy is awesome.

[@blaisegoodman1376]

One thing this video doesn’t show is removing the lower indoor molding. I just remove my sill and found that the sheet rock on the inside of the house was screwed to the sill. I didn’t realize until the sill was out and the Sheetrock inside was blown through. Good lesson I learned, hopefully you can learn from silly me 🤦‍♂️

[@_SYDNA_]

Yep you have a later generation of construction. You'll note that the house in the video has plaster. Ive seen that drywall nailed to sill elsewhere. Windows can be tricky. I'm wondering if a person could sever the drywall nails with a plunge cut through the sill with a multi tool. Not sure. Delicate stuff.

[@Journeyman-Fixit]

This old House craftsmen!

[@zip19145]

The BEST!!!

[@tonyka1984]

50 years from that date, the home owner wants Tom back to replace it again, and Tom gets up to do it.

[@nyratk1]

I'd ask how Tom would be living in 50 years but I imagine he fixes himself up all the time.

[@kalijasin]

Nothing last forever guys.

[@josegarcia303]

Im sure Tom will fix God's house

[@destinyreturns4885]

Beautiful....

[@TheHistoryProject]

great video

[@chuckluchen8972]

Tom’s tip on removing an old sill is great! I hate replacing rotting window sills (and often the brick mold) but once it starts rotting rip the bandaid and replace the entire dang thing. However, I go to PVC every time. I buy the sill and the nose.

[@buzoff4642]

I tried pulling off the brick mold, and the entire window started coming with it. Is the brick mold supposed to come off? This didn't happen with the brick mold around the doors.

[@_SYDNA_]

​@@buzoff4642Yeah, if you look under the paint your brick moulding is stapled to the side jamb (frame). During construction your entire window was inserted, from outside as a unit. Yours is a more recent generation of construction than the house in this video. Your brick mold is also nailed on the outer perimeter, through the fibrous sheathing and into the house framing that forms the rough opening. What I don't know about this style, is how extensively they shimmed the side jamb into place. Any attempt to remove the brick mould, perhaps one stick at a time, should include that consideration. You want to keep the jambs in their current state of plumb and square. Not sure how you provide bottom support on a replacement sill for one of this style but there's probably a way since the jamb will often extend below the sill on these types. Good luck!

[@buzoff4642]

@@_SYDNA_ Experience working on 2 of my windows, window 1, trying to take off the brick molding, entire window started to come out!, window 2, replacing the exterior sill, discovered sill had staples/nails coming up from below into the brick molding. SawsAll to cut the nails/staples going from under sill into brick molding, saw grabbed the nail and ripped a chunk of the lower brick molding out. Yeash, this is no small job.

[@diminett6462]

You are so clever

[@Varifyable]

I never understood tommy using painters caulk for exterior applications. I would use something like OSI quad.

[@ionlyplayps5530]

Love ya’ Tom. Can you show how to operate a makita impact. Please.

[@erniezamora9509]

nice video im building a playhouse for my daughters im new im learning all this stuff ,,, I was wondering if that sill flat fron that bottom how is going sit on the small strip that I see ...that small strip has that same angle just to know ,,

[@a.rs.880]

Caulking job looked bad but I'm sure u fixed that great video

[@marathonlifeH121]

Just one thing though. Calking does not bond well to bare wood as its structural composition has no way to penetrate the wood fibers and eventually will peel off. It's best to always prime bare wood with a strong wood primer before applying caulk. The primer becomes the bonding agent between the wood and caulk. The finish coat will bond to the caulking surface.

[@calvin7330]

Isn't that happening at 3:23?

[@marathonlifeH121]

@@calvin7330 To the sill itself but not to the window framing at 4:10

[@oby-1607]

Yes, Tommy.

[@martinp3371]

So good he didn't even dry fit it first.