If you’re looking to replace your weathered front door, you’re going to need help fitting an external door frame as well.

Keep in mind that this is a ‘controlled fitting’ task as defined by law, which means you’ll have to abide by Building Regulations for doors and be a ‘competent person’.

That being said:

How do you attach a door frame to the wall?

At Door Superstore, we’re here to lend a hand and show you how to fit an externaldoor frame.

Let’s jump right in.


Table of contents:


How do you install a wooden external door frame?

Unassembled external door frame

An exterior door frame is typically made from timber, uPVC or metal, but wooden ones are a perennial favourite because they’re both sturdy and stylish. This is how you go about fixing a wooden external door frame.

Remove the old door frame

Using a crowbar, carefully take out the old door frame. Then, clean and sand the surface. Make sure you remove any leftover nails.

Assemble the new frame

You’ll need a large, even working space ideally at table level. Once you’ve unpacked your external door and frame kit, attach the jambs into the recesses and sill as per the manufacturer’s instructions and make sure everything is plumb.

Put the frame into place

This is the tricky bit when it comes to fitting door frames. Placing the frame into the opening is fairly straightforward, but you then need to make sure it’s flush and plumb.

Luckily, that’s where shims come in. They’ll help you take care of any gaps between the wall and the frame. Keep a 2mm gap at both the top and the bottom of the frame and use the supplied fastenings to fix it into place.

Once again – and we can’t overemphasise this:

Make sure the frame is flush and plumb! It’s tedious, but it makes all the difference in the world. Your spirit level and measuring square are your friends.

Fasten and insulate

Now that your new external door frame construction is in place, it’s time to fix it!

Start with the jambs. Four or five fixings at roughly the same distance will get the job done, depending on the size of the frame. Once these are firmly in place, install two or three at the head.

Pro tip: Stagger fastenings to prevent splits in the wall.

Even so, we still need to find out how to fill the gap between a door frame and the wall.

And here’s the deal:

Weatherproofing is the way to go. Expanding foam and insulation are your best friends. Depending on the product you end up using, you should also consider caulking.

When it comes to how to fix a gap at the bottom of the door frame, the same thing applies. If the gap is wider, you might want to consider a threshold seal.


How to install an external sidelight door frame

Sidelights for external doors are an elegant addition to your home’s exterior design as well as a functional solution which lets natural light into your hallway and helps make it brighter.

What’s more:

Most sidelight frames come with movable jambs, allowing you to choose the size of the sidelights and jazz things up even further.

The good news is:

Fitting an external sidelight frame is a lot like fitting a standard one.

Still, there are a few parts of the process we need to highlight.

Assembling the external sidelight frame

Because they’re a lot larger than standard external frames, most sidelight frames are sold flat-packed to allow for easier on-site storage.

The process of assembly is virtually the same, with one notable extension. Make sure you measure the size of the sidelight or sidelights you intend to fit before fixing the jambs. To reduce the sidelights to the appropriate width, use a plane to remove any excess and sand with fine sandpaper.

Don’t forget to make sure there’s sufficient space for the door when using bespoke sidelights. Leave a 2mm clearance at the top and bottom of the door and sidelights.

LPD Majestic Victorian Sidelight

Fitting the external sidelight frame

Once again, the procedure is very much like what you’d expect with a standard external door frame.

However, since a sidelight frame is a considerably larger construction, you need to check and double-check everything is flush and plumb before you fix it since there’s a lot more that can bend, go off kilter and generally go wrong. Again, due to size considerations, it helps immensely if you have someone helping you.

With that in mind:

Ensure the jambs are vertical from back to front and side to side. When that’s the case, secure the frame firmly into position with appropriate fixings at regular intervals and seal the gap between the frame and the brickwork.

You can now proceed to fit the sidelight(s) and hang the door!


Final thoughts

Fitting an external door frame is something you should plan carefully and well ahead. And even then, a sudden thunderstorm might ruin everything.

The good news is:

Now that you know how to fit an external door frame, you’re ready to take on the task. Check out our guide on how to hang an external door to complete your external door and frame renovation project.

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