Chimney pots, holes and rain!

[dave]

My first time using a roof ladder yesterday to reseat some ridge tiles went ok (scary but ok).

While up there I took a pic of the chimney stack top and was surprised to see this shoddy job on the two liners of our neighbours side. There as can be seen, are several large gaps in the mortar around the liner plates. This cannot be seen from the ground of course and the fixing look fine from there.

neighbours are not the friendliest sort and I don't want to mention it without need, but are these gaps likely to cause a kind of problems for us - eg rain ingress as this is a party wall? Could this cause damp at ground level? We have that problem - our neighbours say they do not - which is clearly an untruth as the black stain on the outside wall is very clear. We have tried various things over the years to fix the damp problem,(wall stuff injected etc) and nothing has fixed it. The stack sits astride the party wall of our houses. As our pots are just normal open ones we obviously get rain down those too - so maybe this is nothing to do with it or maybe both of us need to do something? It's difficult to discuss these things with hostile neighbours. :-( I don't know why the neighbours have liners in there because they don't have central heating - just a gas fire in each room. (Known from more neighbourly days) Thanks

[Bill Wright]

Suggest you put a note though their door:

I've noticed that the top surface of the joint chimney has a number of holes. These obviously need to be repaired. It is not practical to repair one side and not the other, so I intend to apply mortar to the whole of the top of the chimney. Is this alright with you? Note that there would be no cost to yourselves. If I have no reply by ------- I will assume that you are in agreement.

Bill

[Salman Saeed]

Hey Dave, I don't like you very much. Please let me do my assignment. You are boring.

[jim]

while you are at it you could change your cowls to the type with a rain proof lid on "Colt" is a brand ISTR (for starters) cheers JimK

[jim]

see

[Kipper at sea]

For what its worth you might as well bite the bullet and do both. Use washed sand or grit sand, not building sand, at three sand one cement. Don=92t use a sloppy wet mix a stiff mix very little water, as you have to make the material thicker in the centre and slope to the outer edge. You could show the neighbours the photo.

[Harry Bloomfield]

dave has brought this to us :

Gas fires commonly have liners for the chimney.

Looking at the photo and assuming I am interpreting it correctly, I would suggest it would be usual for that entire area to be flaunched.

The top surface of those bricks, plus the gaps between should be covered by a good coat of mortar, such that rain water cannot collect.

Difficult to see properly in the photo, but the furthest two metal(?) pots do seem to have been correctly flaunched at some time in the distant past. That needs to be redone. The flaunching needs to be about

1.5" thick at the centre area of the chimney, then inclined out towards the sides of the chimney, so water is not allowed to collect and is allowed to drain straight off to the sides.

While you are there, check the flashing between roof and chimney. Ours was fine, but we still had some small amount of ingress - so I added a second layer one brick up a few years ago. That seemed to solve our problem.

[js.b1]

heh-heh... there is your cause of damp. About 100-220cm of water ingress a year.

#1 - You need a rain "lid" for the chimney pot.

#2 - I believe SBR in the mortar will help at a roof level.

#3 - Check if you have an upstairs chimney closed off. Reason being if that lacks a rain "lid" your joists will have dry rot, depends on whether it is vented.

On the subject of SBR - B&Q do Cementone for =A315 which isn't bad vs Screwfix (probably higher solids).

[Grimly Curmudgeon]

We were somewhere around Barstow, on the edge of the desert, when the drugs began to take hold. I remember dave saying something like:

The requested URL /pics/potgaps3.jpg was not found on this server.

Additionally, a 403 Forbidden error was encountered while trying to use an ErrorDocument to handle the request. "

Might be handier if you left it up for more than five minutes.

[Tim S]

js.b1 coughed up some electrons that declared:

?

I couldn't find any SBR in Screwfix and I've never seen it in B&Q - though I concede it *is* on their website:

they did round here - best I've had a builder's yard down to is 18+VAT which is why I buy most of mine from - that's well worth it if you need a fair bit. 5l-10l and the delivery kills it.

I've just put 10l diluted 1:4 over my rank kitchen floor after removing loose screed. I poured and brushed and poured until it would take no more.

Seems to have made a big difference - the rather soft old screed in one half has solidified beautifully and (this might be a coincidence) the humidity has sharply dropped from 60-65% to 45%.

Cheers

Tim