Should You Install Windows or Siding First?

It’s most affordable and efficient to install new siding and windows at the same time, but if you only have the budget for one—or are wondering which to tackle first—installing windows is almost always the better option. The reason why is that new window frames can damage siding during installation, resulting in added repair costs. Windows can also be damaged during siding installation, but the repair cost is much lower (typically small repairs to metal caps on your window frames).

Here are the main reasons to install windows first and a few things to watch for as you plan for your project.

Windows Before Siding is Almost Always the Answer

In almost all cases, it’s better to install your windows before your siding so you won’t have to redo trim and siding work. Here's a full breakdown based on the type of new windows you’re installing.

New Construction Windows

New construction windows means adding a completely new window (frames, window panes, trim, and more) where there originally wasn’t one. These are usually installed from the exterior of the house. You may have to remove trim or siding to put them in, so always do them before siding if possible. You may also need to put in a new moisture barrier, capping, or repair the framing. The project often includes waterproofing the exterior, which is best left to a professional.

Replacement Windows

Replacement windows simply means upgrading your existing windows. Because replacement windows are installed from the interior, you could put them in before or after your siding. You won't need to remove siding to install them, but check with your contractor to see if your framing, capping, or moisture barrier needs repair (more on this below). Replacement windows tend to be easier to install and can be a project for moderate DIYers.

Think of your siding as the finishing touch to your project. Leave siding installation for last if possible, so you won't have to rip out and redo any of your work.

Factors to Consider When Replacing Windows and Siding

As already mentioned, the golden rule is windows before siding. There are several components to a window aside from just the frame and glass to keep in mind during installation.

The Condition of Your Window Capping

Photo: enskanto / Adobe Stock

If you’re installing new windows, you’ll likely need new capping around your windows, which is better to install before your siding. Capping is a protective covering, usually made of aluminum, that surrounds your window frames. It seals the gap between your windows and wall, protecting your home from leaks and water damage. 

If you were to tackle siding first, the capping on your old windows could get damaged while removing the siding. You’ll need to recap the existing windows, then cap your new windows when you install them—doubling the expense. Depending on the number of windows, it could cost you several hundred dollars or more to cap and recap them.

Beyond capping, your windows have a moisture barrier that sits behind the siding. If you replace your siding first, you may have to tear off some of the new siding to install your moisture barrier, then reinstall your siding, which could add to the cost.

If you’re hiring the same contractor to do your windows and siding and you choose to do your siding first, ask about free window capping for when they install your new windows.

Do You Have to Remove Siding to Replace Windows?

If you’re adding a window where there originally wasn’t one (in the case of new construction windows), you’ll have to carefully remove your siding to install them. You don’t have to remove siding to replace windows if you use replacement windows and your framing and moisture barrier are in good condition. 

New Windows Usually Solve More Problems Than Siding

If your budget is forcing you to make an either-or decision, windows are almost always the better investment. Not only are new windows aesthetically pleasing, new windows can help insulate your home, save you money on energy bills, and increase the comfort of your home. When you replace your windows, you may also want to reinsulate any gaps between the window and your wall. 

While new siding can look nice and offers your home protection, you can always budget for new siding down the road. Local siding contractors can help estimate how much new siding for your home costs.

Should You Also Consider Insulated Siding?

New windows and siding have the power to do more than boost your curb appeal. They can increase your home’s energy efficiency, which in turn decreases your energy consumption and—more importantly—decreases your energy bill. Siding offers extra layers of insulation to your home, but should you go a step further with insulated siding?

As a homeowner, you have tons of house siding options to make your home look good and protect it from the elements. Keeping factors like budget, climate, and maintenance in mind, you can choose between some of the more popular styles, including:

• Vinyl siding

• Stucco siding

• Wood siding

• Fiber cement siding

• Metal siding

• Stone siding

• Brick siding

If you decide to go the insulated route, you’ll have to stick to vinyl siding. Insulated vinyl siding is one of the more expensive types of vinyl siding. It’s an upgrade from the norm where rigid foam insulation is attached to the back of the siding to fill and block air gaps. Not only does this increase energy efficiency, but it can also soundproof your home from outside noise. Insulated vinyl siding has more material than typical vinyl siding, making it heavier and more expensive to ship and install. The cost of materials and installation will give your siding project a higher budget, but insulated vinyl siding is guaranteed to last longer than most other siding options.

Final Thoughts on Installing Windows and Siding

Above all, your decision depends on what your house needs the most. If your siding is in bad shape but your windows can hold up a little longer, address the most pressing issue first. If both projects can wait, it can make better financial sense to hold off for both to avoid duplicative work and expenses.

Steps to take for successful window and siding installation:

• Ask for contractor referrals from family and friends

• Get quotes from at least three local companies and read reviews

• Ask for the contractor’s advice on the best and most affordable way to tackle your projects

• Check to see if there are guidelines for window and siding installation specific to your municipality

• Look into available tax credits. Some energy-efficient windows qualify for a federal credit.