Could our leak be caused by condensation?

[DrivingMissLazy1]

We have had a leak from our header tank in the loft going down through the fitted wardrobes in dd's bedroom . To get to the tank/pipes we have had to make a hole in the wall.

The plastic tank is situated on a wooden structure (to give a little height as our bedroom is in the loft with an en suite bathroom). The wood is sodden. and from its appearance (and the appearance of the damage to the fitted wardrobes), I would guess that it's been happening at a slow rate for a long time.

A plumber came to look and made an adjustment inside the tank. He thought that the water level was too high and was leaking from a side pipe. He thought it very unlikely that the tank was leaking. All well and good, the wood started drying out that very day. The dripping stopped.

BUT, we still have a drip now and again. It's not continuous. I'm thinking that condensation from around the tank is gathering at the base and then over spilling at intervals. It doesn't look as if it will dry out completely.

Has anyone else experienced this? How can I solve the problem?

Thanks

If it is condensation, you need to look into improving the ventilation in your loft.

No.

The header tank will be at about the same temperature as the air in the loft, so will the pipes unless you have a leak.

Have you looked at it?

Are there beads of water on the outside of the tank, up to the water level and then stopping?

How deep is the water in the tank (1) above the exit pipe (2) below the overflow pipe and the inlet valve?

Is your roof felted (i.e. you can't see the underside of the tiles)? If so, are there beads of water on the underside of the felt?

Do you drape wet washing around your home?

Thanks for the replies.

I'm not very technical. The tank is about 2 foot high. There are 4 pipes at the bottom. There is 1 pipe about 2/3 inches from the top and the water is about 2/3 inches below that.

The roof is felted. It's not wet at the moment but I have noticed beads of water when it is extremely cold.

Having looked at the tank now, it is wet around the outside at the bottom and there is a drip every now and again. The wooden frame is saturated.

For info, the bedroom is quite a cosy room. We have 1 radiator in the bedroom and 1 heated towel rail in the bathroom.

I do hang washing from the bedroom door frames on hangers, not in the loft, but I try and keep a window open when I'm doing this.

I think one of the pipes is dripping.

If it is the feed and expansion tank for the central heating, it is unusual to have more than one pipe at the bottom. This tank would typically be about 18" long x 1ft wide x 1 ft high and probably has a layer of brown mud at the bottom.

If it is the cold water tank, it might typically have two pipes at the bottom, if you have a hot water cylinder, or three if you have a separately plumbed shower. This tank would typically be 2 or 4 feet long x 2 or 3 ft high x 2 ft wide. It probably has a scattering of limescale grit at the bottom.

Crumple kitchen roll and twist it into a rope, and tie it tightly round the ends of the pipe where they enter the tank, usually with a brass fitting. The one that is leaking will make its rope wet.

It is possible for a tank to have a hole in it, but this is rarely seen unless you have a very old steel one that has gone rusty.

For interest, you could post some photos.

Thanks for your time in replying.

I've asked dh and it's a cold water tank which feeds the hot water cylinder and the shower pump.

All the pipes look intact and dry. There's nothing underneath them to indicate water. I'll do the rope test later and report back.

The tank had a raised area at the bottom, like a half sausage shape. It looks like a separate piece, so the bottom of the tank is not one piece of smooth plastic iyswim. It doesn't seem to serve a purpose?

Dh strongly suspects the tank to be leaking but surely that would result in a continous drip?

I don't know what that shape is. Perhaps a stiffener. The tank is probably made of black PVC, it might possibly be cracked, though that is difficult to do, or perhaps there was a nail sticking out of the wood.

A new one is not especially expensive, but due to the leak you will need a new piece of WBP ply for the platform top, and possibly new legs.

You will need a lid and an insulating jacket. The pipe connections will be easier if you get the same size. It will be interesting to look at the old one to find the fault.

Wickes
Screwfix are dearer. Builders merchants and plumbers merchants have them.

this Pegler part 2 is a very good ballcock.