water proofing my exterior walls

[scottishjohn]

now the winter has come with very high winds and driving rain --lots of it 50mph + 

i am experiencing some slight water penetration  in some areas

 what is the best product to coat all theexterior walls with 

without making them shiny and changing the colour of the granite

I suspect there are very small cracks in the pointing and maybe some of stone work

 certainly small as ther isn,t much you could repoint 

and as they used granite sand in the pointing its a real problem to chase them out

 

[gaz_moose]

if you waterproof them and water does get in then how is that water going to get back out?

 

I waterproofed some fence panels with some waterproofer from screwfix, the water just beads off it like a waxed car. some areas of concrete fence posts got sprayed in the same stuff and would repell the water. (i should really have a look to see how it is holding up when its next raining but not minging)  I did read in the reviews that some mad man used it on a brick wall with good results.

[Beau]

14 minutes ago, gaz_moose said:

if you waterproof them and water does get in then how is that water going to get back out?

 

For those of us in very exposed locations when is the water going to get out? We get periods were you get several months were it rains most days and walls hang wet throughout. Our barn was like this and after a few weeks of wet weather the water would run down the inside of the wall. Ended up tanking the inside and lime pointing the outside which worked perfectly. 

 

 

John I have no magic answers sadly.

 

On my workshop which has porous render and pointing I used some Thompsons water seal. It worked for 4 or 5 years but now needs doing again

 

Old buildings can be a PITA

 

Edited Friday at 16:16 by Beau

[Redbeard]

Safeguard Chemicals do 'Stormdry' (I think) and I once used (breathable) Belzona 5122. The hazard sheet had me dressed up like a deep-sea diver! I don't think it has been perfect but it made a significant difference to a house which received much oof its rain horizontally.

[scottishjohn]

so far from my searching I can find a few different products that would work 

however

because granite is non porous it will sit on top if i do it all voer and permagaurd say it it will discolour with age if it is not absorbed

 

so best idea so far is to just paint it on all the pointing joints 

 

I can see now where new stone work has been done that even though waterproofer was added to the mix  it changes colour when its wet 

 

 so first trial will be to coat those areas and see if it then does not change when it gets wet

then we on a winner

 

 my real problem is it was pointed --80-100years+ ago with a mix using granite sand + cament and ground cockle shells -- not lime mortar 

 being a quarry with a stone crusher it is obvious why they used free granite sand and probably some of the beach as well

 it also looks similar colour to the stone work  

 

 which is why all my repairs to insdie walls were sone in nornmal cement mortar

no point in going lime which gould take weeks to dry

 I wanted to get on

 and as there was always going to be a gap to the TF inside any water could evaporate up the gap to the cold roof 

 

 

the small area i have repointed with modern cement mortar , were an absoute nightmare to chip out the rock hard old motar

although the actual walls of course were built with lime mortar

 

they even used the cockle shells in the infilll mortar and small stones in the center  of the walls 

 

I have solid walls .

 

not the usual  outer skin then rubble and an innner skin 

its been mortared up all the way through 

 

 that could acount for why the walls were basically so solid after best part of 250 years 

and why the trees growing around it when i came did not manage to move anything -that and the stone work is built on solid rock  for most of it 

 

 I dug down 3ft outside the walls before i started and it was built to 3 ft below ground level  in most places

 

 I got more water ingress last year   and i am guessing the walls which were open at top for 60 years were still drying out 

  only showing above the downstairs window reaveals

 

 so some special attention will be paid to make sure its  not coming around them 

IF  i was doing it again 

i would fit lead around all  the window openings ,full depth of wall

but that would have meant pulling out all the lintels to do  it 

but If anyone is doing similar and making window openings larger i would strongly advise that is the way to do it 

since istarted asking questions and looking around ifound that was the 100% cure for old stone walls  especialy with lime mortar

 

 I have another water problem with my garage which was built from blocks  attached to the unrenvated part of the building -- 

If I ever get round to doing that then this wall will not  be showing .so iwill try the cheaper silicone cream on there which has a shiny finish    TEMU special  at £40 for 4 kgs as opposed to £150 for premagaurd --worth a try  and disclouration will not be a problem there