Keeping the rain out

[Gib Bogle]

We have a shack in our back yard (some people call it a sleepout) that is fully equipped as a basic bed-sit, with a shower, lavatory, sink-bench, cooker, fridge. It is pretty basic, but can be rented out. Unfortunately the floor is old particleboard (chipboard), and it has suffered deterioration in a couple of places. The worst affected area is just inside the door, at the sides. It is clear that when the wind is from a certain quarter it blows rain through the cracks at the edges of the door, and the water trickles down to where the floor meets the wall. The damage on one side in particular is not restricted to the flooring - the timber supporting the bottom of the door post has also suffered.

I have cut out a piece of the floor (600x1300) and prepared a piece to insert in its place. I'm using the descendant of the old particleboard, a product they call strandboard that is supposedly tougher and more water resistant. I have given the edge and the surfaces within 200 mm of the edge a thorough coating with a two-pot epoxy resin that is designed to soak in. Any other affected timber in the vicinity has received the same treatment. I'm pretty confident that this will do a good job of repelling the water. Nonetheless I'd like to make improvements to the design of the door frame etc to keep the water out as much as is feasible without significant expenditure - I do not want to go as far as building a porch. I'm wondering what is the recommended layout in this situation, and would appreciate any pointers. Since I'm not familiar with the jargon, a site with pictures would be very helpful.

One idea I've had is to ensure that any water arriving at the floor is able to flow through and onto the ground, with the idea that damage will be much reduced if water is not allowed to collect.

[Cash]

Gib,

Could you post a picture of the job on

and then post a link to that picture here? It would give a better idea of the work in hand.

Cash

[John Rumm]

Without seeing a picture its hard to see exactly where the likely weaknesses are. However one common one, is where the door is inset, and there is no rain drip at the bottom of the door (basically projecting piece of wood with an angled top to allow water running down the face of the door to be shed over the front of the threshold, and not onto it.

Rain working round the sides of the door can be stopped with a rubber profile draught excluder set into the frame or door edge.

[Gib Bogle]

OK, will do.

[Gib Bogle]

There is a rain drip. The problem is water entry on the sides. The rubber draught excluder sounds like a good idea.

[Gib Bogle]

Here are some pics.

is a strip of galvanised steel nailed to the sill. A narrow wood strip that was nailed to this has been removed. The new piece of strandboard slides underneath.

Gib

[Jeremy Nicoll - news posts]

better having a door on the outside, larger than the current doorway, that opens outwards? Then it could be made with a compressible seal between its inside surface and the door frame.

[Gib Bogle]

An interesting suggestion. It might be difficult to get a good seal, considering that this shack was built roughly and there's no guarantee that any two timbers are parallel.

[NT]

Looks like a simple problem, the strip of metal fitted doesnt project out far enough to ensure everything drips outside the base. The metal strip also lacks a drip strip, so water will drip not only fom its outer edge. And finally it will trap water agaisnt the underside of the door. If you replace the metal strip with a larger conventionally shaped/placed piece of wood, things should be much improved.

NT

[John Rumm]

That "drip" on the door looks to be a part of the problem. Its not got anything like enough slope on it to shed surface water running down the outside face of the door. It also looks like there is a gap between it and the door. Hence I would expect the bottom of the door to get soaked as water is drawn into the gap, and a certain amount of the runoff to come of the edges of the drip.

You really want something like:

on the face of the door an inch or so up from the bottom, so that it closes over the threshold, and sheds any water well clear of it. (the saw groove in the underside of the fillet will stop water track back along the underside of the drip)

[djc]

Also, looking at it appears that the part of the strip under the door is covering the groove in the bottom of the door that would otherwise discourage drips from hanging on to the bottom of the door and migrating inside. The way it's fixed the water will be collected on the top of the'drip' strip and be directed under the door.

[Cash]

To add to John's post.

I would agree that a bespoke timber weatheboard as John suggested - but it would appear that there was originally a timber sill built into the frame which has either rotted away or been removed.

My method of [permanent] repair would be to:

1 Scarf two new sections of door frame at the bottom (about 12" to 18" long) to remove all traces of rot.

2 As part of the above process, fit a new sill at the bottom that stick out past the outide wall, rebated as the door frame and a weather drip (groove) ploughed into the underside about a quarter of an in wide and deep and about half an inch in from the front edge - bed this sill onto a couple of beads of silicone mastic.

3 Fit the weatherboard as described by John, (bedded onto the door with silicone) and leaving a small gap between the ends of the weatherboard and frame. This will effectively stop all the water from penetrating under the door.

4 As a belt and braces jobbie - you can now eithe fit some of the patent draughtstrips around the door (cutting them to the shape of the top of the weatherboard as extra protection) - or go for the cheaper option of simply fitting a set of timber doorstops (again cut over the shape of the top of the weatherboard).

5 Properly prepare, prime and paint the whole door and frame with at least 1 coat of undercoat and 2 coats of gloss paint (good quality. And this should sort you out.

6 I would also check the sides and top of the frame for cracks and rot, rectify as needed and then run a bead of silicone between the frame and walls.

Hope this makes sense.

Cash

[Gib Bogle]

I appreciate the comments from John, djc and NT about how the "drip" can easily be improved. This will be the first line of attack.

I have to point out that by far the worst deterioration of the chipboard was at the corners. It seems that although some water has been getting under the door, the bigger problem has been water coming in at the edges. Maybe the rubber sealing strip that was suggested will alleviate this. This would still leave a small gap at the bottom, in the corner, but perhaps my idea of holes through the floor allowing this to drain away would be sufficient to take care of it.