Bedding in Window and Door Frames...hair??

[jungle_jim01]

Just looking for some reassurance that i'm on the right tracks with this. I've chipped out the cement around a window ready to treat and re-paint. I'm going to use lime mortar to fill the gap around the edge, leaving approx 5mm recess.
Question1 : i've heard it mentioned that i should use well haired mortar...any reason why i can't use plain lime mortar?
Question 2: If i use hair...how much should i add?

I'm then going to fill the recess with burnt sand mastic, overlapping the wood slightly at an angle.

Is this right?

one more question: should i paint the window frames before or after the mastic has been applied?...can i paint the mastic?

Thanks again for everyone's advice...busy multi-tasking with different bits of the house this week!

 

[Feltwell]

Question1 : i've heard it mentioned that i should use well haired mortar...any reason why i can't use plain lime mortar?

You only use hair for lime plaster, not in mortar - or at least I've never heard of hair being used in mortar.

I'm then going to fill the recess with burnt sand mastic, overlapping the wood slightly at an angle.

Is this right?

The mastic is there to seal the joint between the wood (which will move slightly with temperature and humidity changes) and the mortar (which won't move nearly as much). It stays ever-so-slightly flexible. I fill the joint flush with mortar then put a fillet of mastic on at about a 45 degree angle, but so long as it's sealing that joint and making water move away from it then you're OK.

one more question: should i paint the window frames before or after the mastic has been applied?...can i paint the mastic?

If you're using linseed paint then I don't see why you couldn't paint the mastic, but personally I paint the frame first and put the mastic on after. Apart from anything else I reckon some grains of sand from the mastic will come loose and contaminate your brush & paint.

This is what a finished result can look like up (very) close - window frame finished in linseed paint, pointing between bricks and around frame in lime, with a burnt sand mastic fillet applied to shed water from the joint between the two:-

And from further away:-

 

[jungle_jim01]

Feltwell....thanks for your very comprehensive reply. Really appreciated

 

[Feltwell]

You're welcome. Bear in mind it's just an illustration of what I've done - mostly gleaned from old posts on here - I'm no expert on the topic. Seems to have worked, it's been there 3 years now with no problems - I guess the test is if that's still the case in 50 ! (Beyond that it will most likely be someone else's problem, or I'll at least be too old to care!)

 

[Me!]

I've been reading recently about using oakum to fill gaps between wattle and daub panels and the timber frame of the building, and also around door and window frames. Has anybody ever tried this, or have any good or bad things to say about it? I've found articles that claim to be written by SPAB members saying that oakum is a good and appropriate thing to use, but one can't always believe what one reads on t'internet!

 

[Penners]

Apart from nautical uses, the only application that I've heard of for oakum is in the jointing of old iron pipes. I think it was used as packing underneath the putty fillet.

Since oakum is made from natural fibres (jute?) I wonder whether it might absorb water quite easily, unless it's thoroughly sealed with something else on the surface.

The above are amateur musings - nothing remotely approaching expert opinion.

I'm afraid that, when it comes to dealing in window frames, I am a mastic sinner. I have yet to find anything traditional that's as effective as modern sealants, squirted out of a plastic tube.