Cob Bricks for infil panels

[tumbledown]

Do you think cob bricks would be a suitable product for timber frame infils? Most of mine have been 'repaired' with concrete, or brick with cement mortar. I just thought that bricking them up with cob bricks and rendering with lime/limewash seems a litte easier and requires less skill (which I don't have much of) than using wattle and daub.

 

[middi]

Noble thought.

Unfortunately when they shrink and the studs move they will not stay in the same position , wattle with help of " staves " jammed in the appropriate channels in the studs prevents this.

 

[tumbledown]

Oh, I'm surprised to here you say that. When I was doing some research on the internet, one of the suppliers websites said:

"The advantage of cob blocks is that they can be used at any time of the year, as they are pre-dried, so that little or no shrinkage will occur."

 

[middi]

They would definetely be quicker and easier to fit and provide the correct breathing mechanism for the needs of the building, you can certainly use them as long as you are not concerned about their stability in the studs and prepaired to do some " wedging" with lime putty if any gaps appear.

If I had to use them I would spend a bit of time to countersink cuts in the daub bricks and wedge green oak staves across the studs every three feet or thereabout, the existing wedge channels may be re-used.

If it means saving a nice "chunk" of cash by doing it yourself, go for it.

You may get a grumble from the odd purist , but then they are not picking up the bills.

 

[tumbledown]

Yes, I can see that some of the purists may frown, but the way I look at it is its an awful lot better than whats in there now. I feel more confident of making a reasonable job of it than trying to replace with wattle and daub. Also, I think I should be able to make them pretty secure in the way that you suggest. Some of the panels still have some wattle and daub in them, and if its anywhere near secure I certainly won't take it out - I'm really just concerned with getting rid of the modern concrete and cement.

They seem to recommend using clay mortar/render, but would there be anything wrong with using lime? Is clay just as easy to use and cost about the same?

You are right - it's about finding a method I'm comfortable with doing myself mainly to save money - there is enough going out in other areas!!

 

[biffvernon]

...a litte easier and requires less skill (which I don't have much of) than using wattle and daub.

Good ideas from Middi, but don't get thinking that wattle and daub if difficult. It's really very easy. And you can cheat on the wattle by getting ready made 'screen' from a garden centre. The daub you just dig up from your garden. Add a pinch of lime if you want a really strong result.

 

[middi]

You can use a rich lime/sand render mix, a lime/clay mix, clay on its own or a mix and match of any of the above .
The important thing is that you mix it to a soft malleable putty like consistancy and more important make sure that your substrate(cob bricks) are well soaked with water before application.

Ironically, if you are not a plasterer you end up with a better finish and if you are as useless at proper plastering as I am it will be just about perfect for the building, a nice coat ot two of lime wash and even Henry the VIII would have been impressed.

There isn't a sacrosanct rule about the composition and consistancy of renders, exept that they would hold together in whatever situation they were used and because they were not chemically engineered and without exeption they would have had that breathable quality about them, best of all, they could be dug up next to the building site.

In your situation, and to save money, I would go to the nearest building merchant buy a number of Hydrated lime bags, pre-mixe it in five gallons tubs to a thick double cream consistancy, top it with one inch of water leave it for two or three weeks or use it when I was ready with whatever mix I eventually decided.

 

[tumbledown]

Thanks Middi and biffvernon for the suggestions. I guess what I should really do is have a go on one panel with wattle and daub, and if I find it too much like hard work, give the cob bricks a go.

As far as wattle and daub is concerned, I saw a few web sites where they sold it made up, but it seemed very expensive for a load of mud! I guess the secret is getting the mix right so that it will stay put and not crack up.
I hadn't thought about the garden centre screening - I guess you just tie it into the oak staves using the original slots? Nne probelm is that in a lot of places the original slots are not really usuable due to rot on the service of the timbers. and of course the original staves have rotted away. could you use any sort of hardwood, or is oak best? Where would I get oak staves?

I seem to have talked my way around to wattle and daub!! Like I said, maybe I'll give it a go before reverting to plan A .....

 

[biffvernon]

Don't forget the straw - plenty of it.

 

[middi]

Use oak for the staves, hazel and willow was more common for wattle and to tie it all together do not use modern softwood or (especially) imported hardwoods.
Oak is very easy to obtain in planks which you can cut to size, spilt it to make staves and shape the ends for wedging.

As Biff said, it is not that difficult, the whole process is a bit labour intensive by the time you are ready to lime wash.

Doing it yourself is very cheap really, especially if you want to make a nice puddle in your garden , loads of subsoil, loads of chopped straw, a few buckets of fresh liquid cow manure, an old Gas mask and it will not cost you a penny. :lol:

 

[tumbledown]

Now you're putting me off the idea again .......

 

[middi]

Don't be put off so easy, improvise....., make it interesting......, get the neighbours involved.......
Better still, organise a mud wrestling weekend, the mums to do the wrestling and churn up the daud, the kids to slap it on the wattle, give the dads a bear each, you supervise and everybody will have a bundle of fun.

( Crikey !!!!!, this does not sound as daft as I am )

 

[biffvernon]

Middi is not wrong in his specification of the ideal materials - but it doesn't need to be difficult. An analysis of traditional mud and stud cottages from Lincolnshire showed that all manner of stuff was used. Bits of wood from all sorts of trees, newly felled or recycled, of all sorts of shapes and sizes, were incorporated into the wattles. The poor and humble cottager had to make do with what was to hand.

 

[tumbledown]

Well, I think I'll give it a go - might try leaving the manure out though. Not sure about my neighbour mud wrestling either - although she's not in bad nick for 87 .....

 

[tumbledown]

give the dads a bear each

Middi, not sure how many bears there are in suffolk