Building with SIMS

SIMS by Mannok is a straightforward construction method which utilises the simplicity of single leaf construction whilst enhancing the thermal performance and weathertightness of the building.

The wall consists of a 215mm wide Aircrete thermal block built using either traditional sand and cement mortar or thin joint mortar, externally finished with an approved external insulation system and internally finished with plasterboard on dabs. The insulation thickness will depend on the U-value required and is not limited by a wall cavity.

0.21W/m2K 110mm EPS
0.18W/m2K 140mm EPS
0.15W/m2K 110mm EPS
0.13W/m2K 200mm EPS

Guide based on EPS Pearl Insulation

The Construction Method

Combining high performance elements to deliver a superior building solution

SIMS by Mannok combines the benefits of each building element to work together effectively in a way that is superior to the alternative methods. This construction method is well established and widely used throughout Europe, with most houses in Germany, Belgium, France, Finland, Italy, the Netherlands and more built using the same methodology.

As the Irish construction industry adapts to the challenges of increasing demand for rapid build housing coupled with more stringent energy efficiency requirements, the adoption of this best practice construction method from Europe will become more widespread.


Build using Aircrete Block, Ireland’s most superior thermal block

The single leaf masonry structure is built using aircrete thermal blocks, the best performing thermal blocks available on the market in Ireland for combined thermal and structural performance. The unique composition and technically advanced manufacturing method produces blocks which meet the requirements of Technical Guidance Document A for structure and offer superb insulation properties, with significantly better thermal performance than any other comparable block.

The 215mm (9 inch) blocks used can be built using traditional sand and cement mortar, so the method is very easily adopted by Irish builders using existing skillsets. The blocks can alternatively be built using thin joint mortar.
The beauty of using 215mm x 215mm aircrete blocks in the single leaf masonry substrate is that it cuts the number of blocks required in half compared to either 100mm dense blocks on flat in single leaf construction, or traditional cavity wall construction. This reduction should result in significant time and cost savings on site as half the blocks means half the labour required to build them.

Another key advantage of the aircrete block is it is a low thermal conductivity block; it’s thermal performance is almost 10 times better than a dense concrete block. So by using a aircrete block as the masonry substrate, you’re automatically improving the thermal performance or u-value of your wall. Given that heat loss through walls accounts for up to 35% of a building’s heat loss, this helps to greatly reduce heat loss and results in a much more energy efficient building.

Aircrete blocks used in the masonry substrate have a significant impact on thermal bridging, another significant source of a building’s heat loss. Again, using a low thermal conductivity block as your masonry substrate, you are dealing with your thermal bridges in the junctions throughout your house almost by default.

Aircrete Thermal Blocks

  • Insulates 10 times better than standard concrete blocks
  • Reduces heat loss through thermal bridging by up to 80%
  • More thermally efficient than lightweight aggregate blocks
  • Achieves up to 200% better Psi values than other thermal blocks, such as lightweight aggregate blocks
  • Aircrete thermal blocks’ unique properties achieve a far superior level of comfort for the residents of finished buildings. The blocks’ inherent thermal mass helps regulate daytime heating and night time cooling, making the home a more comfortable place to live all year round.


Build better protected, better performing walls

SIMS incorporates an External Thermal Insulation Composite System (ETICS) that has been used in mainland Europe since the 1960s and has become increasing popular in Ireland in recent years. There are currently 20 NSAI approved external insulation systems in Ireland, and any of those can be used in conjunction with the aircrete block masonry substrate.

Quite simply, the external insulation system includes the insulation layer and then it has a build up of layers on the outside of that to provide your water tightness and render finish.

Traditionally, blockwork in Ireland was cavity wall construction, but with advancements in material and technology, waterproof renders were developed which basically replaces your outer leaf of blockwork, so we have done away with our cavity wall. The insulation is fixed to the aircrete block and the waterproof layer is installed on the outside of that.

A key advantage of this solution is that the thickness of insulation is not limited as it can be with cavity wall construction. With SIMS, you can increase the depth of insulation to the required thickness to achieve the target u-value desired.

ETICS System

  • Achieve excellent thermal efficiency with an ETICS system that wraps the external building envelope in a continuous layer of insulation, providing an effective solution to heat loss through thermal bridging
  • Flexibility in design with various external finish options and no limit to insulation thickness, making it easy to meet or exceed building regulation standards
  • Offers protection to masonry façade against climate and wind driven rain, increasing durability


Build stronger walls, faster

SIMS walls can be built using thin joint mortar, a well-established construction method used throughout Europe. Thin joint technology utilizes 2-3mm mortar joints using a quick setting adhesive in place of the traditional 10mm general purpose mortar.

The 10N mortar gives a stronger bond, which makes the overall wall construction much stronger, so much so that a 9-inch aircrete block built with thin joint mortar is almost 3 times stronger than a 350mm wide traditional dense block construction. The additional strength may make it feasible to reduce the thickness of the wall from a 9-inch block back to 6-inches, which can save construction costs.

If the block layer is familiar with building with thin joint mortar it can also add speed to the construction, but the key benefit here is the added strength due to the increased bond strength.

Get in touch

Talk to one of our experts about using SIMS by Mannok in your next project today.