Patchin up me porch

[zoothorn]

Hi over here- old welsh c1830 stone cottage. Porch to redo just needs lino.. & wall attn.

 

So I pick away at hollow top area here, & it goes on, & on. Ive stopped for advice/ fairly deep in places.

 

There's some damp within the 2ft walls generally, I won't be able to tackle without huge logistics/ & can live with ok, I guess the old grey crumbly mortar I'm easily picking away is so due to moisture rising within the wall. Pick this out, & I'm down to the 1830 "mortar"..IE just soil between the slate stones.

 

Advice please: as its inside porch, no rain on here. Is it just effectively a case of "re-pointing"?

 

Thanks, zoot

 

Edited November 19, 2020 by zoothorn

[joe90]

Pick it all out, take off all paint, let it breathe and point with lime.

[zoothorn]

10 hours ago, joe90 said:

Pick it all out, take off all paint, let it breathe and point with lime.

Hi joe, ok good that's a plan. Right, doing job is no problem. But the materials ive no clue about. Ok, once Ive picked the rest away it'll be double maybe x3 area to repoint you see in photo.. so still a fairly small job, I mean 2 buckets of mortar max.

 

So Buying a bag of cement, Plus a (whatever the minimum ammount of sand) bag or whatever it comes in of sand, then again a bag ( or whatever the min ammount) of lime..... & Im using about a fifth, & binning the rest. Surely not right.

 

I do see mortar tubs of 5l in my homebase place. But never seen lime for sale, even in jewsons ive no clue what it even looks like or how big an ammount it comes in. This 5l tub is far too small Tho & not cost effective to buy say 6 tubs, then add lime stuff.

So ideally I need somehow to buy a midway ammount, between 5l tubs and a full 25kg bag. Surely many non-builder folks have similar size jobs.. so is there some mortar product available, maybe with this lime stuff in?

 

 

[Onoff]

I'd forget using ordinary Portland cement and use proper lime mortar. It's what it will likely have been built with if original. A 25kg bag of the stuff is peanuts (like <£10) but the carriage will kill you and you'll start whining about it on here.

 

Now then, it's coming up to Christmas in the middle of a pandemic and people are stressed. They'll give short shrift to any moaning ? As for waste, live with it, it's a piddly ar$ed little job. 

 

This place does ready mixed lime mortar which will I'm sure be music to your ears, plus it's in Wales. Not sure how close to you. Give them a ring with your requirements and explain the area you have to repoint. Again carriage might up the cost. Maybe a road trip as restrictions allow and you might pick up some tips whilst you're there. 

 

https://www.celticsustainables.co.uk/ready-mixed-coarse-lime-mortar-clm28/

 

Celtic Sustainables are 44 miles from you btw.

Edited November 20, 2020 by Onoff

[PeterW]

As per what @Onoff has said, go get two buckets of the Coarse ready mix lime mortar from Celtic. Do not use cement as you will be storing up issues ..!! It is probably what is causing the damp problems. 
 

The tubs of mortar are only 20kg and is resealable and will mean you can do more patching jobs if needed. Only tools needed to put it into the holes are a pair of gloves and a short length of wood like a bit of broom handle to ram it into the gaps. 
 

Lovely stuff to work with but wear safety specs and gloves at all times !! 

[Onoff]

15 minutes ago, PeterW said:

Lovely stuff to work with but wear safety specs and gloves at all times !! 

 

Indeed, forgot to say that lime can cause chemical burns to skin, eyes etc. If you're using it in powder form then a mask too. 

[joe90]

Wot they said ?. Lime does take ages to go off so don’t worry, it’s not like cement but it’s what your place was probably built with in the first place. Try this.     

 

[Onoff]

A wire brush might be good to get that paint off. Could look really good and make a nice feature. 

[joe90]

Lime pointing is not like cement, neat, flat etc, it’s just rammed in and some lightly brush the surface to get a “cottage” effect.

[Onoff]

2 minutes ago, joe90 said:

Lime pointing is not like cement, neat, flat etc, it’s just rammed in and some lightly brush the surface to get a “cottage” effect.

 

Good guide here:

 

https://www.celticsustainables.co.uk/blog/bag-rubbed-lime-render-finish/

[zoothorn]

@Onoff fab info thanks- never knew such stuff existed, so perfect eg of how useful this site is/ honestly dunno what I'd have done without it.

 

2x 20kg tubs is ideal, & I'll go get it.. post will be a flippin mare!

 

As to the job, my blunt rounded-off-tip trowel I bet is the ticket, small pointy one to force into deep bits. Worked on a site age 18 renovating old barn so actually have some experience of repointing.

 

Thanks, zH

[zoothorn]

2 hours ago, joe90 said:

Lime pointing is not like cement, neat, flat etc, it’s just rammed in and some lightly brush the surface to get a “cottage” effect.

 

Understood joe. What I'm picking off is a few mm's of surface render, it seems, on the face of all the slate: should i replicate this (I think the whole wall is sort of covered with it over all exterior tbh) 'face' addition?

 

Or do I just point between the stone, & just masonry paint directly onto the visible slate to make it all white again-? I'm not going specialist lime-paint stuff/ too expensive, & rest Ive done with dulux masonry paint & looks very good too.

[zoothorn]

Is this sort of ready mix with lime not available in jewsons or usual builders merchants then as a rule?

[joe90]

2 hours ago, zoothorn said:

rest Ive done with dulux masonry paint & looks very good too.

problem with that is it won’t breath, but if your satisfied with the other you have done that’s good.

[zoothorn]

42 minutes ago, joe90 said:

problem with that is it won’t breath, but if your satisfied with the other you have done that’s good.

 

 Ive done the whole house with it.. the render on the extention for eg, is this area different-?

[joe90]

Stone should be allowed to breath, many believe that painting stone leads to degradation. Your render on the extension will be cement so should be waterproof itself so non breathable paint is not a problem . Many old buildings were pebble dashed or rendered to make them waterproof but can lead to more problems than they solve. Frankly with your small area and in a porch may not be a problem so crack on.

[PeterW]

Think you can buy breathable masonry paint now ..?? 

[zoothorn]

1 hour ago, PeterW said:

Think you can buy breathable masonry paint now ..?? 

Was thinking my dulux weathershield is, and it is, but says not suitable for lime render. Recommends Keim brand specialist stuff.. sounds german and expensive.

 

Is the stuff in the tub render?

[PeterW]

Thought this was inside the house / porch not outside..? Decent breathable emulsion would do. 

[Onoff]

17 minutes ago, zoothorn said:

Is the stuff in the tub render?

 

The stuff in the tub is mortar for pushing in between the stones in the wall.

 

A whole new world to tax your brain. Not all breathable paints are the same:

 

https://cornishlime.co.uk/articles/breathable-paints-explained/

[Onoff]

@zoothorn am I thinking you want to render over these stones in the porch? If so you could use the tub mortar stuff I linked but you would need to mix it to a thinner, more spreadable consistency by adding water.

 

Imo well cleaned stones left natural and just repointed would look terrific. 

[zoothorn]

17 hours ago, joe90 said:

Stone should be allowed to breath, many believe that painting stone leads to degradation. Your render on the extension will be cement so should be waterproof itself so non breathable paint is not a problem . Many old buildings were pebble dashed or rendered to make them waterproof but can lead to more problems than they solve. Frankly with your small area and in a porch may not be a problem so crack on.

 

I can understand this: my house 2ft thick 4 walled shell, outside has had some sort of fired-on-from-gun sealed coating-with fine gravel type covering, sort of like pebble dash but far smaller grains & gaps between them.. lord knows what it is. Inside these walls have been super-thick emulsion painted. So both sides not breathable. Removing whole lot is a logistical n'mare. Now whether these coatings have contributed to the rising damp within them, some places/ low down, thankfully not too bad/ liveable with.. or this damp would have come up (I assume by capillary action) regardless I don't know.

 

It defo smells better having removed what I have in porch, & I'm inclined to just white the lime (render?) tub stuff with my dulux weathwrshield even if its said 'I wouldn't on lime render..' in the dulux spiel, as its inside & no rain will hit.

[zoothorn]

8 hours ago, Onoff said:

@zoothorn am I thinking you want to render over these stones in the porch? If so you could use the tub mortar stuff I linked but you would need to mix it to a thinner, more spreadable consistency by adding water.

 

Imo well cleaned stones left natural and just repointed would look terrific. 

 

 Understood- doesn't the mortar stuff have like 3mm gravel in though? occasional 4mm, to add the 'look' to otherwise plain mortar? this wouldn't work as a render onto the stone faces, would it, even adding water?

 

Yes cleaned stone far nicer. But in my case wouldn't blend in to rest of white cottage, or other white 3 sides of porch (those contoured-face-faux-stone bricks). In time I might reveal the stone behind my gothic bed in new room (old c1960 pics show this old outside wall before gravel-dashed-horrorshow added & looks a well built visually lovely slate wall).. but last on list, after whippet.

[PeterW]

@zoothorn is this patch inside or outside the porch..?? If inside then just use ordinary emulsion as it doesn’t need to be waterproof. 

[zoothorn]

2 minutes ago, PeterW said:

@zoothorn is this patch inside or outside the porch..?? If inside then just use ordinary emulsion as it doesn’t need to be waterproof. 

 

yup its inside porch.. so your point being the less thick the paint here, the more possible i'll breathe? or just forget any breathable aspect as its inside-?

 

Assuming emulsion isn't breathable..

 

My builder was grumbling about the super-thick emulsion inside the 4 walls (my main room with stove etc) muttering about not letting walls breathe etc: so wouldn't this be the same for this 'inside' porch area? in which case wouldn't a breathable paint (dulux w'shield) be better than emulsion?