How to Install a Garden Window? – Complete DIY Guide

Installing a new garden window over an existing kitchen sink window is a favorite do-it-yourself project for many homeowners. It doesn’t matter where you choose to install the Garden window, be advised that it’s not a project that can be completed by one person. 

Garden windows are a classic take to planting pot vessels and act like mini-greenhouses. They have an aesthetic look and provide additional lighting and fresh air to growing plants. Many of them are easy to install because most are available in easy-to-install kits that should fit into pre existing window frames. 

window frame

There are many window designs in the market that can add esthetic properties to your garden space. A majority come with four window planes (one on each side). The planes at the top are generally slanted in shape while those at the sides are constructed in line with the window frames.

The size of the window you need is a strong determinant to the number of shelves it can hold. However, structural problems may arise if they are poorly constructed and cheaper models may offer little to no protection against ultraviolet light. 

Here is a complete DIY guide to garden window installation:

Step 1: Take the Right Measurements

Taking the right measurements of the window frame you need replacing with a garden window is the first step to a successful installation.  The right measurements are needed to correctly order a suitable garden window since they all come in different shapes and sizes although a majority of them provide similar elements like a shelf,  4 glass slides including a slanted glass.

Take the Right Measurements

Detach the old window from outside the house by using a suitable knife to cut out the external sealant used to keep the window in place. Do this gently to prevent pulling away from the paint or drywall paper when you remove the window.  Once the insulation and sealants are out of the way, use a mental-cutting blade or Hacksaw cut out the mental blades or screws holding the window in place. 

Next, have someone gently push out the window from within while one or two persons can help to catch the old window when it finally gives way. 

After taking measurements, order the new garden window based on those measurements rather than on the unit size of the garden window. You may have to cover the opening with an appropriate temporary material before the new garden window arrives.

Check to note the size, shape, and orientation of the rough opening left by the old window before proceeding to order a new garden window. 

Step 2:  Inspect the New Garden window

Once you have received the new garden window from where you purchased it, it’s time to do a thorough inspection of what you have.  Inspect all sides and frame to make sure there are no gaps or cracks that will jeopardize the construction process. If you opted for a garden window that opens, make sure the weep holes at the bottom are properly constructed.  The weep holes are a useful feature that allows the passage of water if it so happens to find its way inside the window.

Finally, give the new garden window a thorough cleaning with detergent or vinegar and water before fitting it in place.

Inspect the New Garden window

Step 3:  Try fitting in the new Garden window

The next step after inspecting the window is to check the fit. Even though you took all measures to ensure you purchased the right window there is still no guarantee that it will fit in properly.  If it does fit into the rough frame left behind by the old window, then you are in luck but if it doesn’t fit in properly there are steps to take to ensure you make the most of what you purchased.

Determine the installation height of the new garden window by marking and measuring the center height . This height may be different from that of the old window and the rough opening.  Mark a level across the openings to analyze it. 

If you find out (from your marked lines) that the rough opening is somewhat taller than what is required by the new garden window, it is common practice to install the window at the top and use a proper sealant to fill the gap below.  The innovative use of a sealant beneath will help defend against rain and the runoff of water from the plants. Besides, sealed gaps are less noticeable below than above the window. 

While one person helps to hold the garden window in place, two others can help to fit it in place. Another person should be stationed on the inside to check if there are problems with fixing in the window. 

new Garden window

Step 4: Check and Repair any Seal Damages

You need to check around the rough window opening to make sure that there is no structural damage to it.  If you notice any discrepancies to the structural integrity of the seal, it’s best if you repair it before installing the window. The idea behind properly inspecting the seal is to ensure that you have a completely clean seal around the garden window

Repair any Seal Damages

Step 5: Apply Flash to the opening and around top corners

Flashing is a piece of shiny-like material that is sold in almost any home improvement store. Buy a sufficient length for your new window. Apply this flashing to the sides of the window in such a way that they can’t be seen from the inside of the house.

For the rough opening, apply an adhesive spray on the flashing before using it to cover the edges of the rough opening.  This should help the flashing stick to the opening in other to give a better barrier. For extra protection of the corners, you can double up on the flashing for each corner.

flashing corners of the window

Step 6: Secure the window into place

After you have followed all steps to this stage, it’s time to secure the new garden window to the rough opening.  At this stage, you can work with one person on the outside and one person on the inside to ensure that the job gets done properly.  Position the window in such a way that allows you to secure it with screws on both sides.  If you are not using screws but nails make sure you have someone help you hold it in place before nailing through. 

Secure the window

Note: Be sure that double-check the level of the window before fastening with nails or screws otherwise you run the risk of repeating the process if it is not aligned properly. 

If you are using a hammer, take special care that you don’t damage the fin because you may be inviting leaks if you do damage them.  For this reason, we advised that you don’t use a power nailer because the risk of damaging the fin is high. 

Step 7: Finishing touches

Once you have screwed in or nailed the new window to place the outdoor job is done. If you have done it right, the window will be firmly secured to the wall.  One more time checks to see that the unit is plumb, level up, and in good shape.  Trim out the extra shine that is flushed to the wall.

Nail the new window

Check around the window to reveal if there are gaps to be filled. If the gaps are small, a sealant might suffice to close it up but if the gaps are larger, you may need to use fiberglass insulation.

Inside the house, apply the casing trim that came with the package to the interior of the window. Use the adjustment brackets as directed in the manual to add in the glass shelf from the interior.  Take note that these screens or shelves are majorly removable from the inside for cleaning purposes while the casement handles are foldable for easy access. 

Finally, ensure that the barcode labels are safe in place for future access. You may need them if ever you want to order replacement parts in the future. 

About Jennifer Igra

Growing up in Brooklyn, New York City known for it’s green gardens. Jennifer, a 30 year old gardener and green living fanatic started Igra World to share her gardening journey and increase gardening awareness among masses. Follow Igra World to improve your gardening skills.

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