Altering Oak Veneered Doors

Veneered doors are a great cost saving alternative to solid wood doors. One downside is that unlike solid wood doors; veneered doors only allow for around 10mm or so to be trimmed off each side. This means if you have unusual sized door casings you normally wouldn’t be able to use them and would instead be forced to either fork-out the extra money for solid wood doors, or compromise with cheaper, inferior doors.

I was faced with this dilemma during a home cinema build project (here). This circa 1890s terrace house has some odd sized door casings, hence why I first started looking at solid oak doors. These oak 5/6 panel doors are becoming quite popular and for good reason, they look stunning! At the time of writing this these solid oak doors were available from Homebase for ~£240 each (here). The same style oak veneered doors were available for just ~£80 each (here); a big price difference. At the time Homebase were running an offer for 2 or more doors and I was able to grab 2 oak veneered doors for just £130 with delivery. Bargain! Except they were way oversized for my door casings and therefore could not be used… but I had a plan.

Most veneered doors have a small solid wood trimming block on each side. This trimming block not only allows the door to be trimmed slightly but also provides the strength needed to hang the door on its hinges and fit the latch. If these blocks are trimmed too far it’s not just an aesthetic issue; the screws for the hinges will not grab. The particle board inside these doors will not hold screws like solid wood, especially small screws like those used for the hinges.

In theory you could cut these trimming blocks off and attach some new ones to both hide the exposed particle board and provide a place to fasten the hinges. This would be fine if the doors were being painted, but since the doors were being finished with oil, we required the matching wood grain from the original trimming block.

Cutting Down to Size

Using my Festool TS55 plunge saw & guide rail, I started by cutting the trimming block off one side of the larger sized door, cutting 17mm from the edge of the door (14mm width trimming block plus the 3mm kerf of the blade). This could also be done using a table saw or possibly a good circular saw with a straight edge as a guide. The particle board inside these doors chews-up blades pretty quickly so a spare blade is a good idea before starting.

Top tip: When working on multiple doors always trim the largest door first so if you make a mistake or if the veneer gets chipped at any point the door can still be used in one of the smaller openings.

With the trimming block removed and put to one side for later, the waste section of this side of the door was removed. I only had the 1400mm guide rail when doing this so I had to stop and move the guide rail up to finish the cut, being very careful to get the blade back in the same position each time. A longer guide rail such as the 2400mm would be better suited.

Once the waste section was removed the next step was to re-attach the trimming block to the now smaller door.

To re-attach the trimming block I used my Triton SuperJaws, with a long straight edge to even-out the clamping pressure for the glue.

I worked-out the cuts to get the door to the new size. 735mm is the size of the larger door casing, minus a 3mm gap on each side, minus 1mm for the new veneer for the latch side, minus 14mm for the width of the trimming block in my case.

The other door was done in exactly the same way, but this time the door casing was only 706mm wide, so we need to remove a total of 62mm from the original 762mm width door, including the 3mm gap on each side.

Gluing Back Together

Regular D4 wood glue was used to glue the trimming block back onto the doors. With the surface area this glue is more than strong enough for the job.

Additional clamps were used to further even-out the clamping pressure along the entire length of the trimming block.

Any excess glue was wiped-off at this stage to make sanding easier. As you can see the joint is completely unnoticeable. Once the block was fully glued-up and securely clamped it was left overnight to dry.

The next day the wood glue had dried and the trimming block re-attached. After a light sanding over the veneer joint line the hinge side of the door was done.

Applying the Edge Veneer

A matching roll of iron-on veneer is used for the latch side of the door since it doesn’t hold any weight. This also avoids the need to have a joint in the veneer on both sides of the door. This 10m roll of American White Oak veneer was bought from a seller on eBay for ~£15. This is enough to do both doors, with some spare.

The latch side of the door was cut to size the same way as before, only this time the trimming block is not salvaged. The door at this stage is 1mm smaller than the final required width. The veneer makes-up the final 1mm to bring the door to size.

The veneer is applied using a regular iron set to heat only (no steam). It’s fairly easy to apply the veneer. Starting from the middle, slowly work towards one side, keeping the veneer straight as you go. I used a sheet of plain paper in-between the veneer and the iron to prevent any burn marks from forming.

The key to making sure this stuff works as advertised is to go back over it again with the iron. This is especially important at the edges. I tilted the iron slightly on each edge to ensure a good seamless bond.

The glue is fully set once it has cooled. The excess is then carefully trimmed using a Stanley knife & a small block plane, then sanded smooth.

Fitting the Hinges

Once the door is sanded it can be installed the usual way. First checking the fit, then measuring / marking the position for the hinges (making sure to put the hinges on the side with the trimming block).

I recommend always using ball-bearing hinges these days, they’re cheap to buy online and make the doors seem much lighter and easier to open & close compared to standard hinges.

The doors are hung with 3 hinges. This is especially important for solid doors (veneered or not) not only due to the extra weight, they also tend to be more susceptible to warping / twisting. The third hinge helps support the door & prevent that from happening. It also looks much more professional.

The handle & latch were installed the usual way, being careful not to damage the thin veneer with the chisel. Most door handles these days use small bolts instead of screws, both handles are bolted together through holes drilled through the door. For veneered or hollow doors this is a must. Small screws would simply not grab properly, causing the handle to come loose over time.

The same process was repeated on the remaining smaller door.

For those wondering about the extra wide door casing for this door, this was custom made to fit into this opening after decoupling the room for soundproofing (see here).

Both doors were hung at this stage, but not really complete. As part of the soundproofing process we still needed automatic drop seals installed on each door.

Installing Automatic Drop Seals

With the doors installed I was able to get a clearer idea of where the floor covering would be in terms of height and mark it onto the bottom of the doors. The doors were then trimmed down to size with the Festool TS55 again, allowing ~12mm extra gap between the bottom of the doors and the height of the floor covering.

I used more of the iron-on veneer to cover the exposed particle board on the bottom of the door. While this isn’t needed for visual purposes, if the door were to scrape against the carpet / floor mat / anything else; there is a risk this could tear the veneer along the bottom edge of the door. It’s also a bad idea to leave the particle board exposed as it could expand due to humidity changes and this would effectively destroy the entire door.

I didn’t have the appropriate jig or router bit to cut the slots for the seals so I had to come-up with another solution. I made two right-angle clamping jigs using off-cuts of 3×1 & MDF. These are clamped flush with the bottom of the door and provide a place to clamp the Festool guide rail onto.

The Festool TS55 has a blade kerf of 3mm with a Festool 491952 48 tooth saw blade installed. The drop seals I used require a 13mm slot, so this process requires several passes. I clamped the guide rail in place with a stop guide to stop the saw blade 10mm from the front edge of the door, this ensures the end of the drop seal remains concealed.

After carefully removing enough material to fit the seal into the slot, the seal was cut to length and installed into the door. Both doors received the same treatment.

The seals drop approximately 14mm down from the bottom of the door when the plunger is pressed inwards. This is enough to form a nice draught and acoustic seal against the door threshold.

Oiling & Finishing

With both doors finally done, they were given 2 coats of Osmo 3060 Door Oil. I opted for a clear satin finish with these doors. The oil really brings out the natural wood grain of the American White Oak veneer.

The doors were removed one more time during final decorating, ready for the carpet fitters.