Attic cold water tank - Is it supposed to be completely covered?

ando

Can I ask a simple question, attic cold water tanks... are they supposed to be fully covered over? Is the water inside it supposed to be visible? I have a cold water tank that's insulated around the sides, not underneath (to stop if freezing) and has polystyrene over the top, but it looks like the builder ran out of polystyrene and its about 4 inches too short to cover the entire top of the tank. I'm concerned water vapour is evaporating and causing my attic to have condensation on the felt, which in turn is causing the timber joists supporting the felt and roof tiles to become wet (constantly wet with the recent weather).

fatbhoy

I had to put in these attic ventilation tiles a while back because of condensation on felt (the black membrane lining the inside of the roof in the attic). The condensation was caused by heat rising from the house into the attic and then coming in contact with the cold roof. That condensation was leaking down and onto the bedroom ceiling/wall joins. Fitting the vents immediately fixed the problem.

Now, I don't have my my attic water tank fully insulated either (no lid on it) but the now colder attic space hasn't caused the water to freeze yet, and this is like this about 3 years now, so no problems so far.

The Continental Op

https://www.boards.ie/discussion/2058331637/attic-cold-water-tank-is-it-supposed-to-be-completely-covered

Really its not a big deal. Many tanks are left uncovered and the houses haven't fallen down as a result. If it bothers you then by all means buy a cover or a sheet of insulation board that will fully cover the tank.

10-10-20

The legislation says that attic tanks should be covered alright. If you get the brand and model/size of the tank then a local builder's providers might be able to help with a fitted cover. But as The Continental Op said, it's not a major issue as it's unlikely to be the main source of moisture in an attic. But every bit helps.

jack of all

Attic tanks should be covered to prevent water evaporating into the roofspace and more importantly to prevent the tank becoming contaminated should a bird/ rodent/ insects etc find their way in there! The cover should not be airtight, McAlpine do a neat breather vent, which is fitted with a fine mesh, which is easily fitted to any lid and this is what I've done on mine. Now, I doubt too many people have taken ill by using water from dirty tanks to brush their teeth but why risk it when the solution is easy and inexpensive, as well a being covered under building regulations. I've been in lots of attics over the years and when you see the crap that can find its way into an uncovered tank it doesn't take much convincing to do the job right.

10-10-20

https://www.boards.ie/discussion/comment/121626207#Comment_121626207

Spiders dude. It just took one large one floating to convince me that my two coffin tanks needed lids.

ando

https://www.boards.ie/discussion/comment/121625070#Comment_121625070

Thanks, may I ask you how much it cost for the vents? I must look into this. I bought felt lap vents a few years ago which helped, but since doing the house up, the problem has returned in our attic. I bought 10 more of them yesterday but I think a permanent solution is needed like what you did.

https://www.amazon.co.uk/gp/product/B00M97O5YY/ref%3Dppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1

AmpMan

https://www.boards.ie/discussion/comment/121625092#Comment_121625092

🤣

Crap advice.

They are supposed to be covered now.

Over the years I've seen plenty of dead mice, some dead rats and at least twice dead bats.

listermint

https://www.boards.ie/discussion/comment/121627704#Comment_121627704

A fuller solution is ridge tile replacement with a ridge system. Promotes flow from the soffit right up to top of the roof.

fatbhoy

https://www.boards.ie/discussion/comment/121627704#Comment_121627704

Can't remember properly: I think he was charging about €50 each including installation. He suggested two at the front, and two at the back. That probably would have been good enough. I took a look at other houses around: the council owned houses have been done by the council, and they do three front and rear, so I told him to copy that. He was a roofer guy who also does a lot of council work. He was very good actually; I got him to re-point the ridge tiles before that.

That was probably 4/5 years ago, definitely pre-covid, so I guess prices are a fair bit more now. But it's worth it. Leaks and damp and anything moisture related needs to be fixed ASAP to prevent rot etc..

You can get those vents in different colours, to match the colour of your existing tiles (black, grey, brown, etc.).

fatbhoy

https://www.boards.ie/discussion/comment/121627768#Comment_121627768

The flow you're talking about there assumes you've vented soffits, I hadn't, so I had to go with the vented tiles solution. You'll see a lot of houses have them. I guess years ago (my house is a 1930s/1940s build) you didn't need them because only the ground floor was heated, and now there's a lot more heat generated because of central heating systems, so condensation in the attic is more of a problem now. Well, that's my un-expert take on it anyway. 😀

listermint

https://www.boards.ie/discussion/comment/121627970#Comment_121627970

Ah yes. Many houses built in the 40s and 60s such as cabra kimmage Crumlin had fairly high concrete wall plates put on and no soffit of any kind. Airflow is very restricted there. And manifests itself more now as people make the living spaces below more airtight with new windows doors and in many cases blocking vents.

That air migrates upwards into the attic space. Creating problems that didn't exist 30 years ago when doors and windows we're more crappy and draughty.

RebelButtMunch

Cover it, I found a dead bat in mine.

listermint

https://www.boards.ie/discussion/comment/121628020#Comment_121628020

Missed opportunity for you to evolve and fight crime in gotham

RebelButtMunch

https://www.boards.ie/discussion/comment/121628031#Comment_121628031

Well, I say bat, but I meant something lumpy down the bottom of the tank after I drained it that had a bat like skeleton... pretty grim. Had to give the tank a good wash and bleach.

slinky2000

Yes it should be covered! this is why:

https://www.boards.ie/discussion/2057732902/decomposed-mouse-in-attic-water-tank

tom23

https://www.boards.ie/discussion/comment/121625070#Comment_121625070

Im getting really and condensation after I got the Attic Insulated.... Did this stop it completely?

fatbhoy

https://www.boards.ie/discussion/comment/121629957#Comment_121629957

Yeah, it stopped it. I put down attic insulation myself a good couple of years before that too. Rockwool, 200m thick or so. Then I got those vent tiles put in and since then I've had no problems. It's bone dry in the attic now.

ando

https://www.boards.ie/discussion/comment/121627947#Comment_121627947

Yea I need to get these permanent vents in I reckon. Do you still have that guy contact number? I know you said it was a few years ago, but worth a shot as getting a reliable roofer is gold!

fatbhoy

https://www.boards.ie/discussion/comment/121636762#Comment_121636762

PM sent.

ando

Guys, do you know what this is? It’s a pipe with condensation on the inside of it, beside my cold water tank. It comes up from downstairs toilet??? I wonder if warm moist air is coming up from it??

IMG_9236.jpeg

listermint

https://www.boards.ie/discussion/comment/121638995#Comment_121638995

Is this a bungalow ? And is there a vent stack attached to that particular toilet.

Have seen vent pipes added to the start of a sewer run internally, these usually go out through the roof though.

Bit of a hack job from the 80s...

What's the other end look like?

GreeBo

Its the vent stack for the toilet, you need a vent behind water otherwise the water wont flow. It really should be joined to the main stack and vented outside. But worst case it should be venting outside itself.

Is that toilet a new addition?

Note that there should be no water anywhere near the pipe at that point, its purely to allow air to get in to let the water out (ever hear a sink/bath that gulps when you pull the plug out? Thats one that doesnt have the air behind water)

ando

So its coming from an upstairs ensuite bathroom with shower, toilet and sink. House is built 20 years and I presume its here that long. We're here since 2016 but I've really just only noticed it.. Could it be a source of warm moist air? Should I block it up? I cant actually see the other end or what exactly its attached to. Im guessing its the toilet as the ensuite toilet bowl is directly below it.

And actually, directly above the exit point of the pipe is a lot of damp condensation on the roof felt which is in turn dripping down onto the insulation. The attic has a lot of drips at the moment with this weather and I'm hoping now I've found the source?

The Continental Op

https://www.boards.ie/discussion/comment/121639339#Comment_121639339

You could splash out (hmmm pun almost intended) and stick one of these on the top of that pipe.

https://www.screwfix.ie/p/floplast-af32w-air-admittance-valve-white/42968

ando

https://www.boards.ie/discussion/comment/121639442#Comment_121639442

Thanks, what does this actually do?

The Continental Op

https://www.boards.ie/discussion/comment/121639462#Comment_121639462

It lets air in but doesn't let it out so smells from the drains don't end up in the attic.

ando

https://www.boards.ie/discussion/comment/121639504#Comment_121639504

ok cool. I'm hoping I've identified the main source of warm moist air entering the attic. I'll block it up with one of these and see if that helps. Thanks

DC999

https://www.boards.ie/discussion/comment/121628000#Comment_121628000

@listermint, I live in one of those houses. What would you recommend to reduce the condensation hitting the attic?

All our houses have concrete (or some solid concrete type mass) coming out 90 degrees from the top of the house wall. Extends maybe 8 inches wide and 5 high. And then tiles sit on top of it. I'm describing as I'm not sure if that's what a wall plate is. I won't pretend to know what a soffit is bar an air gap to the attic. But I know you can have strips of soffits or roof tile vents for ventilation. We don't have roof tile vents.

tom23

quick question - i’ve had loads of problems with attic since it was insulated. i came across one of those pipes in my attic. just a pipe that had no flexi duct connected. hadn’t a scooby do what it did. so i could cap it with one of them instead of flexi pipe to a roof vent, which was what i was going to do today. so that valve cover is good? cheers

The Continental Op

https://www.boards.ie/discussion/comment/121668898#Comment_121668898

If you think that pipe is allowing moisture into the attic then putting an air admittance valve on it will stop any moisture getting out. However I feel the value in doing that is minimal as I doubt its the source of your problems. I'd do in anyway just for completeness.

tom23

https://www.boards.ie/discussion/comment/121669088#Comment_121669088

You see I don't know... I had an attic pre isolation never showed any condensation in any form and this is with a broken Extractor Flexi Hose (had come away from Roof and I never realised) and the vent stack never had a flexi hose either. Now after getting attic insulated with SEAI grant, it like a sweat shop up there in places. So Company is coming out today to fix and replace wet insulation. I have bought a 10m Insulated flexi duct for the extractor fan and I was going to buy an ordinary flexi duct for the vent stack, but the valve looks better.

I am hoping the insulation company have answers for me as to why the condensation has built up so badly.

The Continental Op

https://www.boards.ie/discussion/comment/121669114#Comment_121669114

Only answer is that there is no ventilation up there. There is no other reason if its like a sweat shop up there in places.

tom23

https://www.boards.ie/discussion/comment/121669149#Comment_121669149

Yes agree, they must of blocked up the soffit vents etc. I am going to make sure the fix everything.

The Continental Op

https://www.boards.ie/discussion/comment/121669294#Comment_121669294

It was discussed in another thread on the subject but I suspect your attic would benefit from https://www.amazon.co.uk/Refurbishment-Eaves-Panel-Vents-Rafter/dp/B09MG2VC3F/ . I linked to the Amazon listing (not available to Ireland) because it has the installation info in the pictures. Evidently they are hard to find in Ireland.

tom23

https://www.boards.ie/discussion/comment/121669322#Comment_121669322

Cheers... one option I ma looking at is later on in the year is replacing the Bitumen Membrane with a 'breathable' one. I have a price and while right now it's out of budget I hope to get it done. Roofer said he would put in more roof vents. He didn't specify what they were exactly. But insulation company will be here in an hour or so and I'll see what they are going to do and see what they say.

The Continental Op

https://www.boards.ie/discussion/comment/121669428#Comment_121669428

If the roof isn't leaking then I wouldn't strip it off just to replace the roof felt. If you have bitumen then these lap vents will do a good job https://www.amazon.co.uk/Vents-Prevents-Condensation-Attic-Ventilation/dp/B00M97O5YY/.

Bitumen was traditionally on quite a narrow roll so you will have a lot of places you can put them in with no cutting into the bitumen.

tom23

https://www.boards.ie/discussion/comment/121669471#Comment_121669471

Fair play to you, you are a.wealth of knowledge!!!! Appreciate the replies.

tom23

I’m going to ask another stupid question. What happens the smells? do they naturally just go back down the pipe? I had the insulation company out today and they have addressed all the wet insulation and pulled it back from the soffit vents etc.

Now I need to sort this vent pipe and it’s throwing a smell into the attic.

would you if you had a choice.

1. Run a flexible duct to a roof vent.
2. Or fit that product you mentioned in your post.

What is the better thing to do? thanks a million.

The Continental Op

Ideally vent the smell out but second best and good enough is the air admittance valve.

tom23

https://www.boards.ie/discussion/comment/121672339#Comment_121672339

Thanks again... just done a bit of reading on it there... a few thing making sense. We had a bit of a 'smell' upstairs in main bathroom (underneath that vent) which we thought was stale water gathering somewhere. Was driving us mad trying to locate it. So I'm hoping once this is vented it takes car of this issue. I will vent it out... see how that works. cheers again.

tom23

Howdy… so i had roofer back today. We had to put in a new vent in the roof to connect the flexi to out the smell. Literally within a hour the smell was gone .

ando

https://www.boards.ie/discussion/comment/121639442#Comment_121639442

Thanks for comment above, I didnt know these valve's existed and it seems to have really helped. No drops of water on the felt now above the pipe, nothing but dry felt 😀

Valve.jpg