Maintaining an Old Blacksmiths 300+ years old

[wozzy]

Hi everyone, I am a newcomer to this website and hope your help and guidance will put me on the right track!

Just over three years ago we purchased an old blacksmiths which dates back to 1703. This sits on the banks of the river calder in West Yorkshire and by the way does not flood. This river 200+ years ago used to have Salmon running and hopefully those times are very near to coming back.

There are two parts to the property. The main part of the house which was the Blacksmiths and the oldest is two storey. This extends to what used to be a joiners workshop up untill 1983 which is around 200 years old. This is single storey and the total length of the property is probably just over 100 feet.

By the way before we go any further, the property is not listed and maybe this is because of the different ages.

Over the last two decades there have been numerous alterations to the property inside and out which I would to say not to a good standard. We are sorting these out one by one! The pointing where done to the exterior is not to a good standard and maybe the cause of why we have damp in certain areas. Its not just that the pointing is not to a good standard, the person could have researched and come up with a solution to matching this to the existing pointing, instead of mixing a mortar for a new build which is what they have done.

I would like to think that over time we can replace this with a decent match to the original but maybe I am asking too much. I am starting on an area at the side of the kitchen door which is the main entrance to the property. This is one of the areas that we do have damp.

The types of mixes I have come across are endless and some advice points to getting in an expert. The cost would be tremendous and as I am currently between contracts would like to do the job myself.

I have been advised by a friend to only point where necessary and leave the good areas alone, but by doing this means I will have areas that will not match, but I think I should ask the question, does this really matter? Maybe it will add to the character of the property!

How they mixed the mortar 200 and 300 years ago I would not have a clue and I'm sure the products required today are much better than then. I'm not sure whether lime would have been used to some extent but I know the mix does have gravel of some description.

The previous owners who added a conservatory built with the cheapest bricks possible and looks awful. If I had my choice and money I would pull it down and have it built with bricks that are more pleasing on the eye.

I would like some advice on whether you think it is a good idea to re-point the entire house or not?

I would also like a mix that would suit a house of this period.

Just found out the photo size is too big and therefore will have to adjust the size.

Thanks for your help

 

[AMc]

Welcome to the forum!

Given the age of your buildings then any modern cement pointing will be a bad idea, except perhaps in the new conservatory.

Generally - if you have and modern hard bricks and a physical damp proof membrane made of plastic laid in the wall then you can use cement based mortar.
Anything else will need a lime based mortar with NO CEMENT in it despite what builders will tell you about it 'adding a bit of strength' or ' helping it to go off'.

Part of the way the lime mortar works is it allows moisture to move around the bricks and through the wall. It does this because it is more able to move moisture better than the old softer bricks.
Cement is waterproof so forces the water into the bricks or traps it which can cause problems with damp inside and the faces of bricks blowing when get saturated and then frost.

I have a house that has been pointed and patched in various places. I'm quite happy with it and think it adds character. There is nothing wrong with repointing the whole wall/house if you want to. The mortar is supposed to be sacrificial and is designed to be replaced. Your friend is right in that if there is nothing wrong with the pointing then you can leave it alone - the exception being if you have cement based mortar and old bricks where there are signs of damp or the faces 'spauling' (breaking off/crumbling) in which case you should certainly rake it out and repoint.

You may also choose to rid your house of all cement pointing as it's grey appearance doesn't look good next to lighter lime mortar. I'd make that decision after you've repointed a bit and gauged how good you are at it and how much of your life you want to devote to it

If you repoint everything then a match isn't that important. If you want to match in then you're going to need to experiment with sands to find the right mix.

Do a search or two on "lime mortar" and "pointing" here and you'll pick up lots of tips about how to mix it, how to apply it and things to watch out for.
Keep asking questions and I'm sure someone will be able to help you make the right choices for you and your home.

 

[TheForge]

Hi Wozzy,

We too have a Forge in Somerset and are faced with many of the same problems as you have. Strangely enough we also have joinery/carriage building workshops on site! Do you still have the blacksmiths hearth in situ?

I would absolutely back AMc's comments about using lime, if doing the pointing yourself you might be best working with lime putty and well graded sharp sand (not ultra fine builders sand) rather than slaking lime yourself. I'm no expert on the types of mixes to use but a 3: 1 ratio seems common. Have a read of this article:

http://www.buildingconservation.com/articles/mythmix/mythmix.htm

A lot of our pointing appears to have fine 'gravel' in it but it is actually ash mixed with lime, presumably from the forge itself as this would have been a ready supply of pozzolan to encourage the mix to set quicker and slightly harder. In fact the ash changes the colour of the mix to make it appear a lot like cement from a distance. Possibly yours may be the same.

In terms of damp, obviously check ground levels, we have a lot of problems with outside ground levels being higher than inside (especially in the forge itself) and with concrete paths/patios abutting walls and rainwater goods for leaks.

Look forward to seeing some photos!!

 

[skier-hughes]

We ahd the same dilema, repoint it all or only the aprts that needed doing. On discussing it with the old owner, he showed us pictures of when it was done some 20 or so years ago and one section of the house was brilliant white with new lime mortar. YOu can't tell now which that section is.
On looking at cost............ woweeeeee, but the people who were going to do it for us advised against total repointing, mainly on the grounds of why fix it when it isn't broke, may cause more dame than it fixes etc tec
We decided to go for only the bits that needed doing, they mixed up a mortar that is quite close to what's there. If you look close you cna see the bits that are done, but from a short distance it already blends in very well after only one year.

 

[johnandrew]

Hi Wozzy

It's possible we are not too far from each other - I'm between Halifax and Hebden Bridge.

I am currently working on a few trial lime mixes to use for repointing our house once I remove the cement ribbon pointing. I'd be happy to show you what I'm doing if you wish - I'm no expert but have been playing around with lime for a number of years and have been on a few courses.

If you are looking for a local supplier I would highly recommend Womersleys in Heckmondwike

Also the Conservation Team at Calderdale Council may be able to offer some advice.

Regards

John

 

[Moo]

And please hurry up with those photographs!

xx

 

[Andrew Bodenham]

wozzy,

Sounds like you're off on the right track with your experiments. From my experience of lime mortar work here in Northshire I'd recommend using hydraulic lime (say NHL3.5) rather than hydrate, as the result will be more durable when exposed to our weather. I'm presuming that the main body of the property is stone built? In which case you might be dealing with quite large joints. A well graded sharp sand is essential - particles up to 5mm if the joints are big enough to take that. Lime : sand 1:2 or 1:3 or something in between - I don't really think it's that critical. Quality of application is more important; joints very clean, wet but not too wet (depending on absorbency of stone / brick) mortar well mixed, well rammed in, not over worked, kept damp, scraped back and compacted into place with a stiff brush once green, kept damp some more. You'll have to try various mixes of sands until you get a colour and consistency that you're happy with.

Pointing is one of those things that can look so right, but so many builders make a complete hash of it. If you can do it yourself you'll probably get a much better job - and cheaper too.

 

[Penners]

Welcome wozzy.

Judging by your post above, I hope I don't sound patronising if I guess that you don't have much experience of the dark art of lime mortar (neither, incidentally, do I). If I'm correct then you may find some of the terminology used by the cognoscenti above to be a bit daunting.

But don't be put off. If you want to start mixing some lime mortar experimentally, just come back and ask for simple, easy-to-follow instructions. Somebody will oblige, and get you started down the road to a successful and satisfying pointing job. As Andrew says, nobody will do it as conscientiously (or cheaply!) as you will.

 

[wozzy]

Hi Wozzy,

We too have a Forge in Somerset and are faced with many of the same problems as you have. Strangely enough we also have joinery/carriage building workshops on site! Do you still have the blacksmiths hearth in situ?

I would absolutely back AMc's comments about using lime, if doing the pointing yourself you might be best working with lime putty and well graded sharp sand (not ultra fine builders sand) rather than slaking lime yourself. I'm no expert on the types of mixes to use but a 3: 1 ratio seems common. Have a read of this article:

http://www.buildingconservation.com/articles/mythmix/mythmix.htm

A lot of our pointing appears to have fine 'gravel' in it but it is actually ash mixed with lime, presumably from the forge itself as this would have been a ready supply of pozzolan to encourage the mix to set quicker and slightly harder. In fact the ash changes the colour of the mix to make it appear a lot like cement from a distance. Possibly yours may be the same.

In terms of damp, obviously check ground levels, we have a lot of problems with outside ground levels being higher than inside (especially in the forge itself) and with concrete paths/patios abutting walls and rainwater goods for leaks.

Look forward to seeing some photos!!

 

[wozzy]

Hi Wozzy,

We too have a Forge in Somerset and are faced with many of the same problems as you have. Strangely enough we also have joinery/carriage building workshops on site! Do you still have the blacksmiths hearth in situ?

We was told from the previous owner that the Blacksmiths hearth is still in the building. I will explain - The house was underpinned around eight years ago and what is our main lounge now was where the blacksmiths hearth was and wasn't taken out but cemented in but we can't see this. That is my understanding

I would absolutely back AMc's comments about using lime, if doing the pointing yourself you might be best working with lime putty and well graded sharp sand (not ultra fine builders sand) rather than slaking lime yourself. I'm no expert on the types of mixes to use but a 3: 1 ratio seems common. Have a read of this article:

http://www.buildingconservation.com/articles/mythmix/mythmix.htm

A lot of our pointing appears to have fine 'gravel' in it but it is actually ash mixed with lime, presumably from the forge itself as this would have been a ready supply of pozzolan to encourage the mix to set quicker and slightly harder. In fact the ash changes the colour of the mix to make it appear a lot like cement from a distance. Possibly yours may be the same.

In terms of damp, obviously check ground levels, we have a lot of problems with outside ground levels being higher than inside (especially in the forge itself) and with concrete paths/patios abutting walls and rainwater goods for leaks.

Look forward to seeing some photos!!

 

[wozzy]

Thanks everyone for your comments and advice.

I think the idea of re-pointing the whole house was a little adventurous on my behalf and I think the different shades of pointing will add to the character of the building.

The oldest part of the building, the Blacksmiths was built with hand made bricks and therefore a lime mix I think would have been used.

The gable end looks OK.

The back of the house next to the kitchen door with the ivy was pointed sometime ago with what looks like a sand/cement mix and is flush with the bricks so as to look like a continuous flat wall.

The front of the house was patched three years ago and looks awful. This will need looking at!

The newer part of the house which I am told is around 200 years old which I am re-pointing was built with manufactured bricks and maybe a mix of 3,1,1 – 6,1,1 may suffice.

 

[johnandrew]

Wozzy

What are the materials in your suggested mixes, 3:1:1 and 6:1:1? If the building is 200 years old, it is almost certain it would have been built with a lime mortar. Your repointing should also be with a lime mortar - ie a mortar without cement.

John

 

[wozzy]

I'm thinking 3,1,1 sand,cement,lime

I've noticed when taking out the old mortar that the softer mortar behind was damp and as the single storey part of the house does suffer from damp wouldn't it be wiser to revert to a more hardened approach?

I am trying to erradicate the damp issue at the same time.

 

[skier-hughes]

No no no no no, cement will just make matters worse, breathability is what matters not hardness.

 

[johnandrew]

Wozzy

Skier-Hughes is right. Cement is inappropriate and unnecessary. See the following article on the SPAB website about repointing and keep asking questions here.

http://www.spab.org.uk/advice/technical-qas/technical-qa-11-repointing/

 

[wozzy]

Since I started this research I must admit it has been a nightmare.

There are so many answers to what should be a straight forward task.

 

[Schoolmarm]

I've noticed when taking out the old mortar that the softer mortar behind was damp

This is most likely because the mortar you are chipping out is cement and will be trapping moisture behind it. Proof really that cement stops walls from breathing.

 

[middi]

There is no complication and no reason to be concerned Wozzy.

Two shovels full of builders sand ( NOT the washed type that is used for rendering), one shovel full of sharp sand and one shovel full of hydrated lime.

This mixture is simple, cheap and effective and it works wonders on soft bricks. Pointing done approx 25 years ago by myself is still as good as new. Be sure that there is no risk of frosts when it is applied.

To obtain an " aged " finish apply the mortar level with the face of the bricks. 12 (or so) hours later, lightly rake the finished surface with a soft(ish) wire brush, this will expose the sharp sand bits as it would normally appear in aged lime mortar.

Middi

 

[Penners]

wozzy - just adding my voice to others: don't use cement. You mentioned above that on one part of the house hand-made bricks had been used, therefore they would have been laid with lime mortar. This implies a belief that cement mortar was/should be used with machine-made bricks. I urge you not to adopt this view. Your best chance of curing or ameliorating any damp issues in the house lies in using only lime mortar.

 

[johnandrew]

Two shovels full of builders sand ( NOT the washed type that is used for rendering), one shovel full of sharp sand and one shovel full of hydrated lime.

Middi

I have read that sand for lime mortar should be sharp and well graded but as you seem to have had success with the above mix, I might be tempted to give it go. Do you just mix and use it as you need it or do you have some sitting around maturing?

John