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Wood Sill Extension (final)

Posted: December 2nd, 2012, 2:44 pm
by johnleeke
WPSC Window Standard

Number:
Status: [ ] submitted work method, [ ] proposed treatment standard, [x] final treatment standard
Update: 12/2/12
Author: Angel Corrales
References: Bob Yapp repair design
Contributors: John Leeke

Title of Treatment: Wood Sill Extension
Class of Treatment: [ ] Maintain, [ ] Stabilize, [x] Repair, [ ] Upgrade, [ ] Exception
Type of Treatment: [ ] Traditional, [x] Contemporary, [ ] Conservation

Condition to be Treated:
An earlier sill extension's joint has failed, letting water into the wall below.

Description:
Remove the old sill extension, clean up and even out the outer edge of the original sill and fasten on a new sill extension then seal, prime and paint. (This repair method was implemented on Test Windows 1 and 2 at the 2011 Summit by John Bales and Angel Corrales.)

Typical Procedure:

1. Assess conditions and measure for materials needed.
2. Make up extension sill stock.
3. Back prime stock.
4. Remove damaged sill extension.
5. Cut sill stock to fit opening, prime newly exposed wood.
6. Install sill extension. Pre-drill holes for nailing. Apply sealant in joint. Nail sill extension in place.
7. Sand the top surface with a belt sander so the original sill and the sill extension are flush all along the joint.
8. Caulk joint between the sill extension and the wall siding. Set nails and fill with glazing putty.
9. Prime, paint with two top coats.


Materials:
• Southern yellow pine, vertical grain, tight grain.
• Silicone adhesive caulk
• Nails, steel double hot-dipped
• Primer
• Paint

Quality of Results

Best Work: Sill joint is tight and flush with no gaps. Top surface sloped for proper drainage outward. Sealant and paint has even appearance and smooth surface.

Adequate Work: Minor gap (less than 1/8") in joint is visible, but well sealed. Top surface sloped for proper drainage outward. Sealant and paint has even appearance and smooth surface.

Inadequate Work: No slope. Open gap at joint. Gap at joint greater than 1/8". Sealant and painted surface is uneven and rough.

Re: Wood Sill Extension

Posted: December 2nd, 2012, 3:31 pm
by johnleeke
Thanks to Angel for documenting the good work on this sill during the Summit. Here are Angel's work notes, showing how this repair was done on test windows 1 and 2.

Amy, could you please make a drawing showing two figures, the one from the lower left and the one from the lower right corners of the notes? You can use the same drawing method, scale, scan method, etc., as you have used with other drawings, so the style for this matches your other drawings.

Re: Wood Sill Extension (draft)

Posted: December 15th, 2012, 2:02 pm
by oculus
Here it is John. Sorry for the delay. I had the drawing drawn from a completely different angle. I hadn't seen Angel's notes.
Let me know of any changes or if you want the tiff files.
A.

Re: Wood Sill Extension (draft)

Posted: December 15th, 2012, 3:08 pm
by johnleeke
Amy, excellent. Thank you. Go ahead and upload the hi-res tiffs.

Re: Wood Sill Extension (draft)

Posted: December 15th, 2012, 8:02 pm
by oculus
Here ya go. Let me know if they look ok.
A.

Re: Wood Sill Extension (draft)

Posted: December 16th, 2012, 11:28 am
by johnleeke
I can't open these tiff files. I know that I can open your other tiff files.

One of my programs suggests that these tiff files are compressed. Could you see if you can save the files in uncompressed tiff format? Thanks.

Re: Wood Sill Extension (draft)

Posted: December 17th, 2012, 1:53 pm
by oculus
Try this.
A.

Re: Wood Sill Extension (draft)

Posted: December 17th, 2012, 2:02 pm
by oculus
The other drawing has to be re-scanned.
A.

Re: Wood Sill Extension (draft)

Posted: December 17th, 2012, 2:50 pm
by johnleeke
Amy, your second upload of sill_xtension2.tif is not working for me. All three of my graphics programs are reporting "unsupported compression method."

I think we went through this with your tiff files earlier this year and you got them in a format that I could use, but I don't know what you did on your end to resolve it.

If you can try another format, such as PNG (without compression, if you have a choice.)

Re: Wood Sill Extension (draft)

Posted: December 17th, 2012, 2:54 pm
by oculus
Ok. Ill go back and see what we can come up with.
A.