How to Install an Internal Door

If you’re moving into a new home or planning a renovation, you’ll likely need to install new internal doors. Understanding how to install an internal door correctly can feel daunting, but with the right steps, it’s easier than you think. This guide will walk you through internal door installation from start to finish, including tips on preparation, fitting, and finishing.

Before you begin

Before beginning your internal door installation, ensure your doors are delivered and stored properly:

• Check your order: Confirm the correct size, style, and finish, and inspect for any damage during transit.
• Handle with care: Internal doors can be heavy, so always lift with assistance to prevent accidents and avoid damaging the door or property.
• Store correctly: Keep the doors flat, elevated on bearers, and in the room where they’ll be installed. Protect them from damp and dirt.

Step 1: Remove the old door

Carefully remove the existing door and hardware. Take the new door out of its packaging. For glazed doors with paint-and-peel protection, leave the film on until painting or staining is finished.

Step 2: Measure the opening

Measure the door opening, leaving around 3mm clearance at the top and sides of the door and the lining. The bottom clearance depends on the flooring and any threshold strips.

Step 3: Trim the door

Mark the door for trimming so it fits the opening. Up to 6mm can be removed from each edge (maximum of 12mm in height and width combined). Always trim evenly. For fire doors, follow the specific manufacturer’s fitting guidelines.

Step 4: Position the hinges

Use three hinges for stability. If your door frame has existing hinge cutouts, align the new hinges with them. If only two cutouts exist, add a third hinge in the middle.

Step 5: Prepare the frame and latch area

If the existing hinge or latch cutouts are untidy, splice timber to make them neat. Avoid fitting the latch near door mid-rails where the joint may weaken.

Step 6: Plane the door

After trimming, plane the door to size and chamfer the hinge edge slightly to prevent binding. Check the fit frequently during this step.

Step 7: Fit the hinges

Cut and fit the hinges to the door, pre-drilling screw holes for accuracy.

Step 8: Fit the latch and handles

Cut and install the latch, ensuring the handles align correctly with it.

Step 9: Hang the door temporarily

Hang the door with the hinges and handles fitted to test the fit before final finishing.

Step 10: Secure and test

Fit the latch plate to the frame and check that the latch works. The door should open and close smoothly without sticking.

Painting or Staining

Once your internal door installation is complete, remove the door and hardware before finishing. Lightly sand the surface and apply a good-quality paint, stain, or varnish. Don’t forget to treat all edges, including top and bottom. For glazed doors, remove any protective film after finishing.

How much does internal door installation cost?

You might be wondering: how much does it cost to install internal doors? The internal door installation cost depends on factors like the door type, material, and whether you’re hiring a professional. On average, it can range from £50 to £150 per door, with additional charges for complex installations like fire doors or glazed panels. If you’re wondering how much to install an internal door to a garage, expect costs to be slightly higher due to additional fire-safety requirements.

Knowing how to install an internal door frame and fit the door properly can save you time and money. However, if you’re unsure, hire a skilled tradesperson to guarantee a secure and professional fit.

And if you have any questions on how to install an internal door, or would just like to know some further information about the products we sell at Howarth, please visit your local friendly Howarth branch, or contact our customer services on the number 01472 907051.