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Ultra Lime Plaster Base Coat

Lime Green's Ultra lime plaster base coat is a lightweight insulating lime plaster base coat that is five to ten times thermally more efficient than other lime plasters. This makes it the perfect plastering base coat for building renovations, where it gives an additional insulation layer to internal walls and protects against salt damage.

As an insulating lime plaster, Ultra Lime Plaster is such an effective insulator because it contains an aggregate of hollow beads made from recycled glass, which can make up to 55% of its bulk. This replaces the sand conventionally used in standard commercial lime plasters, which means Ultra Lime Natural uses less energy to manufacture and is significantly lighter to transport, so cutting down on distribution costs and energy.

Also, because it is applied as a wet plaster, Ultra Lime Plaster acts as a ‘draught excluder' by plugging any small pores and gaps within the fabric of the wall, something that standard dry-lining cannot do to the same extent.

Ultra lime plaster base coat is applied to walls in the same way as conventional lime plasters. It has good ‘workability' and there are no complicated fixings or problems achieving the right depth of coat.

You can buy Ultra lime plaster base coat through a range of national merchants.

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Data Sheet

View technical information about this product here. If you require any other information please contact us


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Data Sheet

Completely Mineral

One of the great advantages of lime plasters is that they are mineral, without containing anything which will dissolve in water or rot, unlike gypsum and polymer plasters.  Ultra is over 99.5% mineral once it has set, which also means it has the best possible Fire Classification (Class A1)

Thermal Performance

Ultra is the warmest lime plaster on the market: with no cement and a thermal conductivity of just K=0.11 (lab testing at 0% moisture) or k=0.178 (moisture corrected as per the British Standard) it can be an invisible upgrade to your thermal performance while re-rendering. Some typical real world reductions in heat loss on a traditional 9" brick wall would be:

10 mm Ultra = 8% reduction in heat loss

20 mm Ultra = 15% reduction in heat loss

40 mm Ultra = 26% reduction in heat loss

Beware that many insulating plasters only quote the oven-dried thermal values, which can never actually be achieved on site. For better energy savings and thicker build-ups you can consider our Warmshell Woodfibre systems or an insulating hemp plaster cast on site.

Salt Resistance

Ultra offers enhanced resistance to salt crystallisation compared to site mixed lime plasters and cement sand plasters. It isn't designed to block salts coming through, but the very high pore structure and good chemical resistance against salt of the lime means it will cope better than a standard plaster.


Lime Green Solo is a popular option, for a rustic or decorative look. For a very smooth finish, Lime Green Fine Stuff can be used, or a final option is simply to float the Ultra and paint.


For further information regarding Ultra Lime Plaster Base Coat, get in touch with a member of the Lime Green team today.