How do you install window sill molding?

How to Install Window Sill Molding:

The first thing you need to know is that there are two types of window sills. There are those which have a flat surface and those which have a curved surface. These two types of sills differ in their construction.

For example, the curved ones require less work than the flat ones because they don’t need to be bent into shape before installation. However, it takes longer to install them. Also, the curved ones are easier to remove once installed. If you’re not sure which type of sills you want, then go ahead and get one of the curved ones since they’ll cost less and take up less space.

You may also choose to buy your own siding instead of getting it from a hardware store or lumber yard. You can either purchase your own siding or you can hire someone to do it for you. The cost of hiring a contractor will depend on what kind of job you want done.

A contractor will usually charge between $100-$300 per square foot while the hardware stores generally charge between $50 – $200 per square foot. You can use any kind of wood that’s available to you. But if you want something special, then look for a piece of hardwood like oak or cherry. Hardwoods will last longer and won’t crack easily.

If you decide to go with siding, then make sure that it’s strong enough to support the weight of your home. Make sure that it doesn’t sag down due to moisture build up inside your house. You should try to save money where you can.

If you have the time and the skill, you might want to build your own window sills for a much lower price.

Measure the opening of your window and take note of its width and length. Now that you know how big your window is, you can begin deciding on what kind of siding you want. You can choose between wood or vinyl siding.

Each piece should be fastened together tightly and securely. If you don’t have siding, then you need to get plywood instead.


Jack up the house with a floor jack or a scissor-lift. The floor jack is much safer than the scissor-lift because it won’t fall over if you accidentally put too much pressure on it. Wood is traditional but it requires a lot of upkeep and maintenance.

Vinyl siding is made from recycled materials and doesn’t require as much care and attention as wood does.

You can choose to have someone else install the siding or do it yourself. It isn’t very hard, but you will need some basic carpentry skills in order to complete the job.

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Measure the width and length of your window. Also, measure the height from the bottom of the sill to the bottom of where you want the new window to be. The height of this area will be equal to double the width plus three inches.

For example, if your window is 60 inches wide, then its height (and width) will be equal to 2x(60)+3, or 2x(60)+3, which is 126 inches.


Find a board that’s at least as long as the width of your window (not including the frame), and as wide as the height of your window (not including the frame). The board needs to be at least two inches thick.

You can pay someone else to do this for you or you can do it yourself. If you plan on doing it yourself, make sure that you have either a table saw or a circular saw with a guide. You may also want to have a Jig saw, and a sander.

You can use any kind of wood you want, but make sure it’s the right size. (Remember, use at least a 2×6)

Once the frame is ready, place it inside your window. The frame should be resting on the window sill, with both side boards resting on the window jams.

If you need to, use clamps to keep it in place while you work on the siding.

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Get your boards and position them so that the top of the board is at the bottom of the window (The bottom of the window in this case, being the area where your window sill is).

Once you have the first board placed, put another next to it making sure there’s a space of about an inch between the boards. Keep on laying the boards down until the bottom of your window is completely covered in wood.

Now, space the boards out about an inch from each other and continue to place them down starting at the top of your window and working your way down.

When you reach the bottom, cut a piece of wood to fill in the last bit of space at the bottom. Use wood glue or nails and screws to keep everything in place.


Once the frames are installed, you can begin to fill in the empty spaces with insulation. Most windows have an R-Value of around 3.5.

In most areas, this won’t be enough to keep the house warm during winter and may make the room hotter during summer. The solution to this problem is to increase the R value of your window up to around 26 or greater. This can be done through several methods. The first, and most expensive, is to fill the empty space with glass insulation. This is a very dense material that fills up the empty space and ensures that there are no air pockets. The downside to this is that it is very expensive and isn’t readily available.

The second option is to use expanded foam insulation. While this doesn’t guarantee that there won’t be any air gaps, it can be forced into all the space, and will act as a great insulator. It is also much cheaper than glass insulation.

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The last option, and the one that I recommend, is to use fiberglass insulation. It’s fairly cheap, although not as cheap as just filling the empty space with wood, and does an adequate job of keeping the heat inside.

Fiberglass insulation is either sprayed or blown in to the empty space and then a special spray is used to make sure that all the air gaps are filled in.

Once you’ve finished adding the desired amount of insulation, you’re ready to move on to the next step.

Step 4: Installing the Interior Part of the Window

Once the frame and the gaps are filled in with wood and fiberglass, you’re ready to move on to step 4. The interior part of the window often gets overlooked when doing a window replacement, most likely because it’s not visible, but it’s just as important as the part that is seen.

First thing you need to do is cut out the inside part of your window. In order to do this, you will have to remove the window that is already there.

You’ll need to remove everything except for the frame.

Once you’ve finished removing everything, it’s time to cut out the part of the window where the window pane used to be. Start by measuring the width and height of the opening of your window frame. Then measure the width and height of your interior window frame (The part with no glass) and subtract the first numbers from the second numbers.

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