Frequently asked questions
Your kits are made from mdf. This really isn't a suitable material for outdoor use is it?

Only if you mean regular mdf. When this material gets damp it expands, or "blows", and is ruined. However the material we use is moisture proof mdf, commonly known as "green" mdf. If this material absorbs moisture it doesn't blow and can be dried out. The mdf manufacturer recommends sealing the edges of green mdf to prevent moisture ingress (more about this below).

One of our original buildings (an engine shed) has been outside for three years. The material is still fine and the building has needed only a little maintenance in that time - principally re-gluing a couple of the roof pieces that had come adrift. No fault of the mdf.

Just after Christmas we put together one of our lineside building kits, sealing the edges as described in our instructions. The building then went outside, otherwise unpainted and untreated, and it has survived snow, sleet, rain, frost, and sunshine. We showed the building to visitors to our stand at the National Garden Railway Show at Stoneleigh this year and they were most impressed.

And perhaps most impressive of all, we have a Raven Square frontage kit outside. When it was examined after the heavy rain we had before Christmas it looked decidedly water-logged inside. This was the result of inadequate sealing (not following the instructions properly!). The building was brought inside and put on top of a central heating boiler for a few days. We weighed it when we brought it in and we weighed it again after it had dried out. The final weight was 0.75kg lighter than when the building was brought in! The building didn't suffer any adverse effects despite absorbing the equivalent of a full wine bottle's worth of moisture - proof indeed that "green" mdf is suitable for year-round outdoor use.
What do I seal the edges with?

The mdf manufacturer recommends using diluted pva glue. (We presume exterior grade pva glue.) However, based on the recommendation of Ian Sharples, an award winning model maker, we use thinned glass fibre resin (diluted 50/50 with cellulose thinners). We have also recently tried using Thomson's Water Seal. We'll let you know how it goes. Incidentally, for best results we also seal the surfaces of the mdf as well as the cut edges. This should minimise the opportunity for moisture ingress.

In the past we tried using liquid rubber (used for repairing the roofing felt on flat roofs) for sealing the edges. This seemed like a good idea, but in practice it didn't form as good a seal as thinned fibre glass resin.
What should I use to stick the buildings together?

Our indoor display models are put together using industrial grade "superglue" (Cyanoacrylate). We don't know how well this would perform outside in the long term, so the buildings on our railway are put together using Evo-Stik "Serious Stuff Wet Grab" adhesive. This works very well.
What about sticking the textured plastic sheets to the mdf?

Again, Evo-Stik "Serious Stuff Wet Grab" adhesive. The sheets on our display buildings are stuck on using industrial grade "superglue" (Cyanoacrylate) but this doesn't give all over coverage and "Wet Grab" is better.
Any other tips?

Well, based on our three year old engine shed, apart from sealing the edges, which is essential, painting the building inside and out seems to assure a long life. The other thing that seems to be important is to make sure the joint at the apex of the roof is well sealed and covered over.
What paint do you use?

Dulux "Weathershield" exterior masonry paint is available in small tins and various colours and this is what we use, very successfully. You will need two or three coats to make a good covering, but it's worth the effort and it dries quickly. There are both smooth and textured finishes available. The textured finish looks very good.