Limestone Walling for Beginners

The wall beside the front gates progresses slowly.  This is not really because of the poor weather, as I have done a lot of work on it in this last week by second guessing the weather forecast.  The lack of speed is simply because building a proper stone wall is a laborious task which cannot easily be done more quickly, especially by an amateur such as me.  The new wall is hidden behind this fence panel (photo right) to the left of the front door, and extends to the boundary wall on the extreme left.

Before finalizing the design of this wall I did a fair bit of research to see what sorts of wall could be described as the local style.  Although this was interesting, I actually got confused as there were so many slightly different styles which I had never noticed until I took fifty pictures of various local walls!  I therefore settled on the obvious idea of making it the same design as the boundary wall that it meets, although I am adding on the top some coping stone which was removed from the front wall where I put in the driveway (see photo at the bottom).  The end of the wall has to be 17" wide as that is the width of the reclaimed cut stones with pintles for gate hinges (which I bought last year), and the lower one can be seen in place in the photo left.  As the coping stones which I have are 14" wide, the wall will have to narrow slightly both as it rises and as it goes further away from the hinge line. It also has a slight bend in it, which is why the courses look odd in the photo left (NB It is about 27" high here and still needs pointing).  The finished wall will be about 6 ft high at the end for the gate hinges (i.e. the left hand end in the photo), and about 8 ft long, so that I will have a pair of gates beside the front door, and then the wall will extend across to the external garden wall.  The soil rises as you get closer to the garden wall, so the height above ground will be only about 4 ft at that end; to aid security, I will plant blackberries which are growing freely here - they are really nasty so will be quite an effective deterrent.

I am using a 3:1 mix of sharp sand and Castle NHL5 plus a small amount of building sand for the mortar of the main structure; possibly I could have used NHL3.5, but I wasn't sure so went for the "eminently hydraulic" NHL5 (see the Mike Wye website for explanations!).  For pointing I shall use a 3:1 mix which I have already tested and made up, using local sharp sand and lime putty as this will give me a good match with colour seen locally.  I think I read somewhere that it helps a wall if the outermost mortar is more porous than the internal mortar.

Technically I am repairing the wall, as I found the old foundations of a brick wall whilst digging the foundations for this one.  I am embarrassed to admit that the foundation is comprised of concrete blocks as I want this wall to be solid and to outlast me.  I know that lots of old walls stay standing for umpteen years but I bet that the people who put those up had a lot more skill than me! 

It might not be obvious but it is essential that limestone is laid in the correct orientation: the strata in the stone must be horizontal, as this is how the sedimentary stone was formed; if you lay it on its side then the strength is reduced significantly and it might well split.  It helps a lot if you can lay each course using stones of a uniform thickness, and you should also try to use the thicker stones at the bottom of the wall (but that might just be to save lifting heavy stones up high!).  The shape of the stone is clearly important as well; I am building a wall of squared faced limestone by re-using old stones which are already essentially in the shape of blocks.  You can do a wall using rubble, which sounds terrible but means that the blocks are not squared and you probably have to use the natural face caused when the stone is split.  Even then, you still want to build it in courses, but they can go up and down gently with a varying thickness, rather than being in neat horizontal lines.

I am trying to make the wall look as though it has been there for ages by using weathered stone which looks grey rather than yellow, and the source of a lot of this was the driveway cut through a low wall (the right hand gap in the photo, right).  However, that only gave about 20 sq ft of stone, and I probably need 50-60 sq ft.  I have also got some various bits of stone which were lying around this property, plus some yellow stone from under the kitchen floor, plus some more grey bits found when digging the foundations for the extension.  More recently I had some good fortune when the digging of a soakaway in the churchyard two weeks ago yielded another 5 sq ft of lovely squared blocks which have dried out and look very good.  [Top tip: sodden limestone and bricks dry out very well if you remove all the earth and mortar, leave them outside (raised off the ground on some old batten) and brush it periodically with a stiff hand brush.]

One obvious reason for the poor rate of completion is that my own skills are limited - after all, like many other tasks on this house, I have never done this before.  Although I have a good idea of how it should be done, there is no substitute for experience.  Another reason is that the supply of stone is limited (and the stone has been spread over a good area of the intended lawn), which means that the choice of each stone is quite time-consuming, but pre-sorting the stone by thickness helps speed things up.  I try to choose all the stones for several feet of a single course before mortaring them all in as that seems to speed things up as well.  I do actually find the job quite satisfying; this is possibly due to my mathematical bent and my liking for jigsaws.  I also used to play Tetris and am good at packing the car for going camping.

My final reason for the slow progress is that it is very tiring work.  My elbows feel strained and I have been sleeping very well recently.  Hopefully I can make more progress in the next week or two, and I'll post details when I unveil the wall to the public!