NHL renders
Somes recommended mixes
| Background Prepare background Re-point and dub out as necessary with compatible mortar. | Stipple Coat Cast or sprayed on only Must be used on poor suction, dense / smooth surfaces. Leave as Cast Cure 2-4 days | First Coat Cast, spray or lay on. Well-keyed background. Control suction. Leave Keyed Cure 4-7 days | Second Coat Cast, spray or lay on. Control suction. Straightening coat. Leave keyed. Cure 7-10 days. Finishing coat in 2 coats work. | Finish Cast, spray or lay on.Control suctionFinish as required Cure min 3-10 days |
|---|---|---|---|---|
|
Cob / Earth |
Mix 1A - Sand SG3-5mm |
Mix 1B - Sand SG10-15mm |
Mix 1C - Sand SG5-10mm |
Mix 1C - Sand SF / FS3-5mm |
|
Wooden Lath |
|
Mix 2B/3B - Sand SC12-15mm (8-10 cover) |
Mix 2C - Sand SC8-10mm |
Mix 1C - Sand SF3-5mmMix 2C - Sand SM5-8mm |
|
Metal Lath |
|
Mix 3B - Sand SC10-15mm (8-10 cover) |
Mix 2B - Sand SM10-20mm |
Mix 1C - Sand SF3-5mmMix 2C - Sand SM5-8mm |
|
Soft Brick / StonePorous Blocks |
|
Mix 1B - Sand SC10-15mmMix 2B - Sand SC10-15mm |
Mix 1B/C - Sand SC/SM10-12mmMix 2B/C - Sand SC/SM10-12mm |
Mix 1C - Sand SF3-5mmMix 2C - Sand SM5-8mm |
|
Medium Brick / Stone / Blocks |
Mix 2A/3B - Sand SG*3-5mm |
Mix 2B/3C - Sand SC10-20mmMix 2B/3B - Sand SG**10-15mm |
Mix 2C/3D Sand SC/SM8-12mmMix 2C/3C Sand SG**6-10mm |
Mix 1C - Sand SF3-5mmMix 2C - Sand SM5-8mm |
|
Dense Brick / Stone/ Blocks/ Concrete |
Mix 2A/3A -Sand SG3-5mm |
Mix 2B/3C - Sand SC10-20mmMix 2B/3B - Sand SG**10-15mm |
Mix 2C/3D Sand SC/SM8-12mmMix 2C/3C Sand SG**6-10mm |
Mix 1C - Sand SF3-5mmMix 2C - Sand SM5-8mm |
* Stipple coat optional, depending on background suction and conditions.
** For harling applications.
| Lime | Mix A 1:1.5 | Mix B 1:2 | Mix C 1:2.5 | Mix D 1:3 | Mix E 1:4 |
|---|---|---|---|---|---|
|
NHL 2 |
1A |
1B |
1C |
1D |
1E |
|
NHL 3.5 |
2A |
2B |
2C |
2D |
2E |
|
NHL5 |
3A |
3B |
3C |
3D |
|
| Sands | Type | Particle Sizes |
|---|---|---|
|
SG |
Sharp gritty |
5mm down to 0.075 |
|
SC |
Sharp coarse |
3.35mm down to 0.075 |
|
SM |
Sharp medium |
2.36mm down to 0.075 |
|
SF |
Sharp fine |
1.18mm down to 0.075 |
|
FS |
Fine soft |
0.8mm down to 0.075 |
Note: a wide variety of finishes can be achieved by adopting different binder and sand mixes to satisfy all requirements.
Coat thickness and optional mix ratios are related to exposure and background conditions and are the responsibility of the designer.
Curing and protection must follow best working practice. See Protecting Lime Mortar.