lime pointing?

[william127]

I have been asked by a new customer to price upre pointing a patio, but they would like me to use a mix suitable for the age of the house(1500s). I have been advised that i need to use a hydraulic lime mix and have found the ratios i need online but does anyone have any advice please, is this a sensible mix etc, and has anyone done anything similar? This is a new client and an interstiing project, so i want to do my research and get it right, thanks, william.

[Daniël Bos]

Did they have patios in the 1500's?

[normandylumberjack]

" Doth thou thumb thy nose at my Patio my lord?"

 

The shaming of the shrew- William Shakeyspear 1530AD.

 

 

 

Use a highly fired hydraulic 5 lime, as it will be harder and more resistant to weather and traffic.

[niftysteve]

as far as i know you wouldnt use lime on or below ground level

[hedgesparrow]

lime mortar you need quick lime the lime centre nr winchester will be your best bet for resurch and resourcing the correct material sorry for spelling

[farmer rod]

I have been asked by a new customer to price upre pointing a patio, but they would like me to use a mix suitable for the age of the house(1500s). I have been advised that i need to use a hydraulic lime mix and have found the ratios i need online but does anyone have any advice please, is this a sensible mix etc, and has anyone done anything similar? This is a new client and an interstiing project, so i want to do my research and get it right, thanks, william.

 

Lime mortars shrink more than those made with cement, so you need to keep the work very well wetted while the joint goes off, and it does take longer to go off. Hydraulic lime comes in various grades, the hydraulic refers to the fact that it can set under water, normall lime requires the action of CO2 from the air to make it set.

 

I have only used limes in stone and brick walls and some in plastering, so I cannot give you a mix for pointing stone. However if you have an old lump of mortar, dissolve it with brick cleaner, wash carefully then try to work out how much coarse and how much fine sand there was in the mix.

[agg221]

Hydraulic lime is fine in damp conditions due to the chemical set. There are different grades which determine both set and ultimate hardness - as with a cement mortar you don't want it harder than the stones. Unlike a cement mortar, you should use sharp sand so you need enough lime in the mix to fill up the gaps between the particles. This means you can't deviate much from 3:1 - 2.5:1 so you control hardness by selecting the correct grade. This is likely to be NHL5 but could be NHL3.5 if the stone is soft.

 

If you want the right look, use well washed sharp sand, keep the mix stff and ram it down the joints hard with a blunt ended stick (I use an old bit of ceiling lath). Overfill the joints slightly above flush. Once the mortar has gone crumbly, scrape off flush and level with a stick, allow to dry a bit more until part-set and brush off with a stiff brush to remove the lime from the surface and expose the aggregate - this makes it weather much better.

 

If you want the look with less effort, use snowcem instead of lime as it doesn't need to be kept so stiff or rammed in. You do need to be very aware of timing for brushing off though - lime is next day or later, snowcem is a couple of hours or you're too late.

 

Alec

[Woodworks]

Much as Alec just said. Lime pointed our barn with NHL 3.5. Very slow to set where near the ground due to moisture so would imagine pointing on a patio will be slow to set. If it is sunny you may need to damp the face down to stop the surface drying too fast.

 

Brushing off time is critical. Too soon and you smear lime over the face stone and too late and it's a bu@@er to shift. I used a wire brush but traditionalists use a stick. Loads of information on this site Lime putty,lime mortars,lime plasters and limewash supplied at unbeatable prices by Mike Wye & Associates,Suppliers of Natural Building and Decorating Products

[Woodworks]

Just remembered a couple of other things.

 

Give plenty of time for mixing more than cement mortar. Because of the extra time be cautious to avoid adding excess water. On the up side you can work it up for many hours without it going off and it is lovely to work with.

 

I would tell you the mix we used but I wrote on the back shed door and have since painted over it

[Climbingmagnus]

I'll second what agg221 has said.