Repairing a Chimney Capping

Can you add a picture?

Will this help? The guys who did it maybe can spare some advice.

I would not ignore the steel but prepare it with an anti-corrosion coating so you can re-use it.

Dont fall off the ladder. Ms Cat still needs you to get all them birds out of the chimney (unless you do a permanent cap like in the video)

Happy hunting cementing.

Pictures?! You want the moon on a stick!

OK then

It's not the actual chimney pot that's the problem, it's the concrete slab... maybe there's a problem of terminology... ah, maybe it's the chimney terminal? Some guy on Youtube calls it a chimney crown... wha'eva'

Anyhow you can see the poor state of it from the pic.

Ah, I found this vid which is pretty helpful.

Del

OMG, I just realised that I am missing a chimney crown all together. I will watch this thread and see if can install one.

For me it looks like you can get away without the mesh/steel reinforcement, no?

How about a hammered copper shroud around it, filled with grout?

Do they have precast caps available over there?

about 35 years ago, my dad had had the same issue.... When we started with the cap, but ended up we didn't stop till we were in the basement of the house.

Yes we ended up replacing the whole chimney.

Wasn't that bad, it was a 2 day affair. But we bought the precast cinder blocks and flues. And rebricked on the top.

I thought it was cheap, but it weathered pretty good and still going strong.

just be careful, don't want to have to call the fire department to rescue a cat off the roof.

Don't think I could carry a precast slab up a ladder... and I'm too stupid to think of pulling it up on a rope.

Nope I've not seen pre-cast ones.

Del

on a side note,....

when I visit my dad whose 90 years old.... I can visit him every week, and in November on the most windy cold day, he would want his chimney swept..... He was good enough to not stoke the furnace for a few hours for me......

It was still a pain in the butt with the wind blowing, hot ash coming through and a very steep pitch roof.

since then, when I'm visiting in the summer I'll climb on the roof to check out the chimney to see if it needs repairs and run a brush through before its needed.

I've repaired caps like that with ready mix. You also need to apply some type of sealant to it when you are done. http://www.conproco.com/ConproShieldM.htm I do the sealant every year and it will prolong the life of the cap considerably.

I would continue the brick work up in a pyramid style with copper wire #10 solid strand run through the structure crisscrossed on each level, then wrap the structure with copper mesh screen and attach the wire to the mesh to hold it securely....then coat it with mortar and seal it .....

...or maybe something like this...

...or this...

Or this - I've done a couple of them using a piece of blue stone for the cap...

Woo, now that is cool.

I've Just been up there... what a state!

No need for chisels, most of it came away in my hand. A couple of bangs with a 2lb hammer to break the big bits and it just all lifted off.

Mrs Cat wouldn't let me lob the chunks down onto the lawn so I had to bring it down bucket full at a time.

At least it's down to nice clean brickwork... no worried about steel, there was only one random rod corroded to nothing. I've turned the terracotta pot upside down so it's stuck down the hole and won't blow off. I'll maybe get it cleaned up and the shuttering up today... better check the weather don't want the shuttering to get soaked.

I think it's really a case of a stitch in time saving nine...

I'll maybe get some pics.

Del

I never tire of the beautiful handiwork by people who obviously take great pride in their work.

One word of caution, relying on the chimney to break your fall is ill advised as you may uncover an unseen weakness in the brickwork at the most inopportune time, and have the chimney meet you on the ground! Secure your rope to a more robust anchor point.

Ha, the problems have all changed now!

There was a damp proof course of some bitumen based material, probably roofing felt which has all decayed. Should I replace it and if so, with what?

I've turned the chimney pot upside down and stuffed it down the hole to stop it falling off as it's now completely free.

Interweb suggest lead or copper sheet.. yeah right... have you seen the price?

I have EPDM sheet but that would probably not withstand the temperatures of a chimney... mind the fire doesn't get used, and if it were reinstated then a liner should be fitted. Should I use roofing felt (I prob have some lying around somewhere in the garage), but again flammability issues).

Am I being too fussy?

I could run the DPC to the outer edge of the terracotta pot and a little way up the outside of it so it doesn't actually enter the chimney. Or I could stop it 1/2" short of the pot.

So there I was worrying about steel reinforcement when the real prob' is DPC

Maybe just leave out the DPC, it will still be better than it was before!

This shows how much rubble I had to bring down... mind it's keeping me fit, and Mrs Cat has made me a nice cup of tea.

Hope you'r not to exhausted reading this...

Del

Is that a tiled roof? Nice...

Tiles are very common in that part of the world, especially with younger buildings.

Slate used to be commonplace. Nowadays it tends to get used for niche applications such as in the repair or matching of heritage buildings' roofs in adjacent new-build. Slate is difficult to obtain new, being largely imported from Spain these days or being obtained second-hand from building materials recovery specialists. Tiles are easier to obtain, much cheaper per unit area though, of course, are much heavier - a factor that must be taken into account when proposing the re-surfacing of roofs on buildings that have been designed for something lighter; a family member told a story of a slate-roof house that had had tiles as a replacement and the upper walls bowing-out and cracking with the extra weight.

Tiles have a minimum pitch angle; slate can be used successfully at shallower angles than tiles and have fewer limitations on sizes.

Oops. Login didn't work.

So your THE anonymous poster!

That would be telling...

;-)

Maybe Mrs Cat could catch the pieces as you toss them down?!?

I'd just clean off what's there and redo it with ready mix and a good sealer.

By-the-way, you might consider masking off the top course of bricks and then some paper/cloth to cover the rest of the chimney before you start putting mix up on top...saves a LOT of cleanup later!

Got it cleaned off and the pot re-positioned and held in place with a small fillet of cement.

I'll put EPDM sheet over the remaining brickwork and concrete over that to about 1.5" thickness at the edge unless someone can give a different/better recommended thickness?

One irritation was the corner of a top corner brick breaking away as I was cleaning it up. Some idiot had put a masonry nail about 1" from the corner (probably when there was a TV aerial or some such) . To keep the look of it I glued it back in place with rapid epoxy (don't tell the others). I'll make good the pointing under it and above it before doping the concrete.

Del

Epoxy is fine...I've used this stuff with good results too...

http://usa.sika.com/en/residential/residential-home/product-type/multipurpose-adhesives.html

A few thoughts... Thanks for sharing. I haven't worked brick in years. Very nice looking English bond brick house. The chimney mortar looks to be @ a 1/2 " joint size with a very course sand base. I would expect at the age (guestimate) you would be starting to see some ingress of moisture. Tight counter flashing but the mortar doesn't give the appearance of a tight bond at the brick. The bucket would have scared me as it appears underbuilt for the task. A heavy rubber bucket with a thick steel wire suited for the task would be my preference.

Most importantly -By chance was it Yorkshire Tea?

Cheers, yeah, the big bucket wasn't on the pitched roof, I used the small rubber wire handled buckets which are a managable weight.
The big bucket is just something to put the rubble in before It's taken down from the flat roof to groundlevel.

The flashing will get repointed when I've done the crow/cap/whateveritscalled...

Del

I learned at a very early age the importance of knowing your limits,and basic physics.

I was a cocky know-it-all teenager,and my first day on a construction job I was told to

remove the excess leftover brick form the 2nd story of a building.

I was not allowed to throw them off,because of breakage.The owner was very frugal.

Analysing the situation,I noticed there was a beam and pulley that was used for

hoisting material up,so I thought,why not use it to take the bricks down.

I found an empty nail barrel,about 25 gallons size or so,as best I can

remember.

Things are still kind of fuzzy about the whole shebang,but I will do the best

I can.

I used a rope and pulled the empty keg to the top,and tied the end off to a stump.

I then went on the roof and filled the keg with bricks.

Went back down to the stump,and to make sure I had a good grip,I wrapped the rope

around my hand several times.

I then untied the rope,intending to lower the barrel slowy to the ground.

This is where a heretofor unknown force called gravity took over.

The barrel of bricks weighed twice my weight, and when the rope was untied,it

started down at an accellerating rate,and I started up at the same rate,and I met the

barrel somewhere about half way.

I was stunned by the impact,but I was determined not to fall,I refused to let go of

the rope,even when my fingers jammed into the top pulley,and they stayed jammed

with the rope burning through, until the barrel hit the ground,breaking the bottom of

the barrel out,and dumping all of the brick.

Of course,now I weighed more than the empty barrel,and it started back up,and I

started back down.

Once again I met the barrel half way, but I still held on to the rope,even though I

nearly lost awareness of my surroundings.

Finally I hit the ground, on top of the pile of bricks left for me by the barrel, and I

was thinking: Whew! I'm glad that's over.

But it wasn't over.

I must have blacked out briefly upon impact,and had let go of the rope.

Then of course the barrel started back down.

I don't remember anything after that,except an image burned into my retina and

brain of a barrel getting larger and larger,right before the lights went out.

I woke up with a bright overhead light shining in my eyes,and faces hovering over me.

Apparently I had set some kind of record for the least amount of work hours before

filing a claim for workman's comp.

It was due to this accident that I began to study physics in earnest.

One never knows from whence his inspiration will come.

II've seen that story before, somewhere.

Solar heating systems, chimney pot repairs, bow-making - is there no end to this cat's talent? ;-)

The chicken wire is just to help keep the mortar together as you apply it and until it drys. Don't worry about the rust once you've encased it in mortar it shouldn't rust that much and as long as the mortar doesn't crack up it shouldn't matter. The cap is really to prevent water from getting down between the bricks and in winter freezing and cracking or allowing steam to form if it gets really hot. Since it's not an active chimney the freezing and cracking is your main worry. If you put a good concrete sealant on it after it dries you'll probably help prevent future issues.

Cheers, good idea.

Del

Mr. Cat, I would suggest two constructs for the sake of longevity:

1. You could use a Non-shrink/non-metallic grout. Concrete or mortar is very porous and will absorb water, and you'll end up in the same boat again a few years down the road. You don't want to let water infiltrate down into the supporting brink and mortar because of the freeze-thaw issue will produce popped chimney brick courses.

Make sure you provide at least a 1/2-inch thickness of grout at the perimeter lip, and taper up no less than a 1/4-inch per foot slope. Much higher slopes are recommended to shed rain.

If you want, after the grout cures you can paint the surface with a bituminous paint to add additional level of protection.

2. You could fashion a sloped galvanized sheet steel cap to cover the top of the chimney. I would recommend brazing the corner joints, as well as providing at least an overhang (past the brick faces) with a drip edge. I would recommend a slope of at least 1/2-inch per foot upwards. Use a good high quality silicone rubber sealant at the clay flue-cap interface and along the underside of the drip edge.

You should provide a bituminous paint on the steel cap to help prevent future corrosion.

Whoops , too late... I've done it

I put on an EPDM sheet as a DPC tacked down to the cleaned up and patched cement with waterproof PVA. I've cast 1.5" of concrete on top of that with a good slope. I'll re-do the pointing when the concrete has cured and the shuttering removed.

I may over paint the concrete with a sealant and I'll run a bead of sealant around the pot/crown join.

Ooooh look you can see one of my solar hot water panels too.

Del

Good style Mr. Cat, good style!

I came to the party late with my suggestions...

But a hearty thank you for your suggestions because some of us lurkers out here are thinking our chim-chimmeny caps are in need of attention before real damage starts to occur.

You are very welcome Sir.

Consider this for sealing the mortar:

Sodium Acetate.

A little known sealant that is also used in potato chips to give that salt/vinegar taste.

It also used for instant reusable cold packs.

Non toxic,lasts a long time.

You can buy Sodium Acetate on line,or if you are a real DIY er you can make your

own from vinegar and baking soda.

Instructions can be found on web.

I have included a link to get you started:

Nice work, by the way.

http://www.sciencedaily.com/releases/2007/08/070806101941.html

Cheers, I shall buy some salt and vinegar crisps to consume in the name of research

Del

Be sure you wash them down vigorously with a pint!

Interesting, too bad Cal-trans didn't know about this before they built the new Bay Bridge, could have saved a lot of money and red faces!

The question is, how does it stand up to the "lick-taste" test?

Is Cal-Trans the company that receivedhuge bonuses for getting it done ahead of schedule?

My mistake,... I just got done reading it.

I don't want to hijack the Cat's thread but the conundrum of the bridge is scary at best. The main anchor bolts have been a problem from the day they planted them! I haven't been across it and won't let family members go across it. And sure as hell don't want to be around it during any sizable Earth Quake either.

http://www.theruststore.com/Rust-Converter-Gallon-P40.aspx

Del, above is a link to a site that markets rust conversion chemicals.

I have used this type of product several times to treat oxidized rebar and other steel that was still salvageable rather than to replace it.

There are several name brands that will work well as they are pretty much all composed of the same chemical makeup.

I have also purchased this same chemical in the LASCO label from Home Depot in smaller quantities so I am sure the local hardware store either has some or can get it.

Cheers, it turned out there was only one skinny bit of steel rod and it came away with all the concrete. I haven't put any steel in as the concrete is sitting on a good solid bed of brick and I don't think it reed reinforcing.

Ta for the link.

More pics when the shuttering comes off.... I hope it looks ok

Del

Great pics! Your home is awesome and beautiful. I deeply favor brick & tile homes and wish all homes would be built as well as they are.

Have a great weekend and stay safe!

I realize it is now too late for this piece of advice,but it may help someone in

the future.

There are 3 types of mortar mix,at least in the USA.

They are type S,type N and Type M.

The first two are low strength general purpose mixes.

The type M has extra portland cement and is very high strength,made primarily for

below grade applications,where strength and water resistance is required.

If type M is not available, add 2 scoops of Portland Cement to each bag of mortar.

This will bring it up to and surpass the Type M specification.

Before modern materials were used for sealing basements,the recommended method

was a thin layer (1/8") of 50% portland cement and sand,spread uniformly over the

surface,and kept wet for at leat 24 hours,followed by a second coat of same mix.

If done properly,and kept wet during the cure period,it was waterproof and did not

crack,since the underground temperature and moisture is fairly constant once

back filled.

I have seen water tight basements 50+ years old with no leaks or cracks using this

method.

I never could replicate G-ma's secret recipes, the directions were something like, 2 pinches of this or 1 pinch of that, but she never told us what the volume was of her pinch Now she's gone ......

1 Scoop= 1 rounded shovel full,using a standard(ahem!) pointed shovel.

The amount is not super critical,so approximate values are ok.

I am sure there is an engineer out there somewhere that will tell you to weigh the sand,

measure moisture content of the sand,consult a chart for the proper amount of water

using a calibrated bucket,etc,etc.but I have found that close is good enough unless you

are building a nuclear plant.

Sorry, I couldn't resist

Careful what you wish for. One lightning strike and you'll get your wish, in spades.

Vinegar works good at cleaning up the splashes...looks good too me!

Nice job Del! I know who PM on my next job GA from me