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How Much Damage Does Replacing Windows Cause

How Much Damage Does Replacing Windows Cause

How much damage does replacing windows cause, and how can we avoid it?

Why focus on the negatives? We’ll show you how to optimise your home in all the right ways.

At Boyland Windows, the best views are through our windows, and we know that proper installation is key to excellent performance. Otherwise, you never know how much damage replacing windows might cause. Installing windows the right way will increase comfort, energy efficiency and security.

If the following sounds too complicated – please don’t worry. This is what our team can do for you, without damaging any walls or windows!

1. Removal of Existing Window

Score the paint or varnish between the window frame and the drywall jamb extensions or interior trim. If the existing window can be removed by cutting around the perimeter, use this method to remove the window. Otherwise, start by removing the screen. If the sashes or panels are not removable, remove the glazing with a putty knife or small pry bar. Be careful.

You don’t want to find out the hard way how much damage replacing your windows can cause!

Now soften the glazing adhesive with a heat gun. At the same time, press a deglazing wheel between the glass and sash or frame to separate the glass from the glazing adhesive. Carefully remove the glass sashes and any division bars. Cut through the frame in several places. Use a pry bar and a block of wood to pry the window frame away from the wall.

2. Rough Opening Verification

Clean the existing frame and surrounding wall to ensure it is dry and free of dirt, oil or debris. Check the opening is level and confirm that the window will fit in the opening – with 1/4-inch to 3/8-inch space left around all four sides. Confirm that the window frame is deep enough to extend onto the brick or siding with exterior sealant application. Also, check whether the new window frame will overlap onto the wall framing far enough to permit the frame screws to be driven into the framing. If it will not, the interior finished material should be trimmed back, removed, or a drywall installation clip can be used.

3. Preparing the Opening

Cut and bend a piece of flashing. Apply sealant across the framing and edge of sheathing at the top and along the ends. Fasten the flashing to the top, wetting out the sealant. Continue the sealant down each jamb. For brick, place a bead of sealant along the side of the brick, close to the back edge. For siding, fill the gap where the back of the trim and sheathing meet. Cut two pieces of flashing tape 12-inches longer than the width of the opening.

Apply the first piece of flashing tape over the bottom of the flashing and 6-inches down each side. Cover the exposed edge of the drywall jamb extensions, if applicable. Apply the second piece of flashing tape across the bottom of the opening and 6-inches up each side. If the building wrap is accessible across the bottom, hold the flashing tape over it. This may require loosening the siding. Otherwise, you will find out how much damage replacing windows can cause.

Cut two pieces of flashing tape equal to the height of each side. Apply one piece on each side of the opening. Place and level shims on the sill 1/2-inch from each side, as well as under any mullions. Secure the shims with roofing nails or flashing tape. Drill pilot holes in the new window frame if not factory pre-drilled. If using drywall jamb extensions installation clips, secure them to the opening to align with each pre-drilled hole in the window.

4. Setting the Window

Apply a continuous 3/8-inch tall bead of sealant on the surface of the flashing tape that covers the drywall jamb extensions, if applicable. Centre the window in the opening on the sill shims. Check to make sure that the window rests against the drywall jamb extensions and makes contact with the sealant, if applicable. Place shims and adjust them accordingly. Keep the sash-to-frame gap of the window space – or reveal – consistent. Drive screws at each pre-drilled hole. Check for smooth operation and make any necessary adjustments.

5. Interior Sealant Application

Use a low-pressure polyurethane window and door insulating foam sealant to create an interior seal. Insert the nozzle 2-inches into the space around the window. If the drywall jamb extensions are not present and foam is applied from the interior, insert it 1-inch. Also, place a 1-inch deep bead of foam to allow for expansion. Apply sealant where the new window frame and the drywall jamb extensions meet, if applicable. Shape, tool, and clean away any excess sealant.

6. Exterior Sealant Application

Insert backing rod in the space between the window and the siding, or brick, and top-flashing. Apply a continuous bead of the window and door installation sealant over the backer rod, sealed between the window and flashing. Do not seal over the flashing. Shape, tool and clean any excess sealant. Voilà! You’re done!


Get in contact for an in-depth discussion on avoiding window damages during replacements

First impressions are everything. Make yours count with Boyland Windows.

If we were to sum up Boyland Windows, we would say we are a solution provider for all your home improvement needs. We work with many product partners to supply you with the best possible option to use with your GOV Double Glazing Grant.

We cover:

Ashley – Barton on Sea – Boscombe – Bournemouth – Brockenhurst – Burley – Burton – Christchurch – Dorset – Ferndown – Hampshire – Highcliffe – Hurn – Lymington – Lyndhurst – Milford on Sea – Mudeford – The New Forest – New Milton – Poole – Ringwood – Southbourne – West Parley – Wimborne – Winton

At Boyland Windows, our friendly advisors can point you in the right direction for the best windows and doors. Have any further questions? We’re open Monday to Friday, 8 am – 4:30 pm.

Please feel free to get in touch by calling 01202 499499 or use our contact form.


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