A1. BELOW GROUND
Conclusions of 2-year Canadian Study:
“For the conditions recorded over the two year monitoring period in this experiment, the SPF insulation specimens installed as exterior basement insulation showed stable and sustained thermal performance in the soil.
The moisture management capabilities of these unprotected SPF specimens below grade were confirmed, both by the sustained thermal performance over the two year period and the low moisture contents of the specimens measured on retrieval.”
1. Swinton, M.C.; Bomberg, M.T.; Maref, W.; Normandin, N.; Marchand, R.G.; In-Situ Performance Evaluation of Exterior Insulation Basement System (EIBS) – Spray Polyurethane Foam, 2000. 41 pp.(A-3132.3)
CSIR recommendations for Sub-Structure Insulation
“Foundations can be a significant source of heat loss and require appropriate insulation to ensure proper thermal performance of the building envelope. The proposed new building standards and regulations for energy efficiency in buildings in South Africa will, require that ground floor slabs are insulated to ensure proper thermal performance.
Exterior below-grade insulation is a unique challenge and opportunity for performance improvement because it performs many functions. It can provide insulation between the building assembly and the ground while protecting the structure from environmental challenges such as compression and expansion due to frost action, and moisture and water from wet soils. This means that particular care must be taken when selecting an effective insulation and damproof system to ensure that it enhances the overall performance of the building and maximises energy savings associated with heating and cooling.
One way of achieving the correct insulation performance is to use a closed-cell spray polyurethane foam (ccSPF) insulation and waterproofing system. A typical application of ccSPF would entail casting a rough concrete slab, covering that with a layer of ccSPF, and applying another layer of concrete to form a sandwich.
In addition a layer of ccSPF can be applied to both sides of the foundation walls: this method provides excellent thermal performance while also providing moisture and water resistance to the below-ground building-envelope construction. Particular attention must be paid to choosing the appropriate foam density and thickness especially in sub-structure applications.”
SA Green Building Handbook, Vol.2, p.176 – Llewellyn “Sub-structure -van Wyk, Senior Researcher, CSIR Built Environment Insulation”
A2. UNDER FLOOR
SANS 10400-XA:2011 “Energy usage in buildings” (National Building Regulations):
4.4.2 Floors This new regulation states that where any under-floor heating system is installed, the heating system shall be insulated, to prevent heat loss down through the floor.
The ideal position for the Floor Insulation is above the concrete Floor Slab, and below the Screed. With this method, the Thermal Mass of the Screed is utilised to help regulate internal temperature, by storing some of the heat (heats relatively quick). The insulation prevents this stored heat to dissipate down through the floor, containing all heat inside and causing elements to switch off much sooner for maximum efficiency.
SPF’s advantages over other under-floor insulations:
- Seamless Insulation means no Thermal Bridging.
- Seamless closed-cell layer adds additional moisture barrier.
- Seamless layer means no water can get trapped underneath.
- Fully self-adhesive to concrete floor gives a solid base for subsequent Screed and Finishes, enhancing durability.
- Liquid installation makes it possible to get 100% seamless cover to any shapes and around protrusions etc. in the Floor.
- THERMAMASTA SPF density and compression strength is designed to handle light foot traffic even without covering with finishes – overall assembly is much more solid, and Screeds can be thinner than on loose boards.
- Best R-value in industry just for the SPF Material, means thinner layers can be applied to reduce overall thickness.
Insulation on the inside of external walls is the best solution if insulation from outside is not an option. Even older buildings with listed facades or those worth preserving often have low thermal insulation which can be improved by more than 60% by internal insulation. Installation is also comparatively cost effective because no scaffolding is required for the building and it can be applied on a room by room basis. After a short curing time, the insulating layer is clad on the room side using plasterboard or timber boards, decorative exposed brickwork or plastered brickwork. Comparatively little living space is lost due to the excellent insulating performance of even a thin layer of RIGIFOAM.
This is a typical construction solution in Europe, where in situ rigid polyurethane foam (‘ccSPF’) is the only insulation material which can achieve the maximum water resistance level on masonry façades without any other requirement.
Many buildings are designed with double skin masonry for visual or structural reasons or as protection against extreme weather conditions.
The cavity is given an insulating layer so that the cold air between the facing wall and the lining wall does not then cool the internal ‘skin’.
A seamless, self-adhering insulation layer is installed onto the outer face of the inner wall ‘skin’ at the same time sealing the surface against moisture ingress.
Tie-anchors for the outer skin is sealed around by the foam, ready to receive the outer wall ‘skin’, without compromising water- or air-tightness.
Stone facings can be clad over the insulated and sealed block walls, without any compromise in severe weather conditions.
The external insulation behind a curtain wall or with ventilated cladding can be used both in new buildings and refurbishment of existing buildings. The cladding protects the external components against weathering and as a decorative facade gives a designer, lots of options.
Metal supports for the cladding are prefixed to the wall then RIGIFOAM is sprayed onto the wall and around these fixings. Depending on the type of cladding, a system of vertical timber laths or aluminium support rails are then installed to attach the curtain wall. There should be a 2 to 4 cm ventilation gap between the curtain wall and the insulation to dry off any moisture on the ‘rainscreen-cladding’.
Light Steel and Timber frame construction is typical in Great Britain, USA, Canada, New Zealand, Australia, etc.
As the name suggests, this method of construction relies on a light frame as a basic means of structural support. The outer leaf is typically Fibre-cement, brick, render or timber, to suit the local district or planning requirements.
RIGIFOAM is applied between the studwork of the light frame for thermal insulation. The low thermal conductivity of the material has clear advantages here because despite low wall thicknesses, a comparatively high insulating performance is achieved.
The cured spray foam guarantees additional support and stability for the whole of the light frame construction. Studies in the US have shown that the ‘racking’ strength of light structures can be increased by as much as 300% with the incorporation of SPF insulation.
The “in-situ” application of the foam also guarantees air tightness of the structure, something traditional insulation methods cannot do.
Combining SPF with Light Structures allows for uncomplicated individual facade design possibilities.
A4. CEILINGS & SOFFITS
SPF is the ideal solution for insulation applied ‘overhead’ to underside of roof sheets, concrete soffits.
- Self-adhesion with exceptionally strong permanent bond.
- ‘Liquid’ application allows perfect sealing around and over any hangers, ducting, pipes, installed overhead.
- Economical installation of high-performance material.
On underside of Steel Roof Sheets
- Noise from wind, rain and thermal shock is greatly reduced or eliminated altogether.
- Seamless coating ensures no condensation can from underneath roof sheets (this ‘hidden’ form of corrosion can often be as bad, or worse than external corrosion of roof sheets)
On underside of Roof Tiles
- Noise from wind, rain and environment is greatly reduced or eliminated altogether.
- Best possible method of insulating a tile roof, as roof is sealed air-tight (‘wind-washing’ is eliminated).
- Significant structural enhancement of the whole roof, by bonding all components together.
- Burglar-proofing built-in, as it is almost impossible to lift tiles from the outside.
Any shape of roof imaginable can be insulated with SPF External or Internal – SEAMLESSLY
IDEAL POSITION OF ROOF INSULATION
Where possible, insulation placed on the outside of a building envelope, will have the most benefit, for Energy Efficiency and Protection of the building (see table below).
Closed-Cell SPF is especially suited to be applied externally, and due to its seamless nature, is unmatched for its ability to perform these duties.
But even a roof insulated from underneath, will gain additional benefits, which only SPF can offer (see table below).
SPF AND ROOFING SUBSTRATES
SPF is self-adhesive onto virtually any substrate. Only a few may require a primer, e.g. bitumen and ‘fresh’ galvanised steel.
During the ‘liquid’ state, the material locks mechanically onto the surface at molecular level, creating an exceptionally strong permanent bond.
WEIGHT OF SPF ON ROOFING
At a density of about 45kg per cubic metre, SPF weighs only 1,125 kg per one square metre, installed at a thickness of 25mm.
SPF has excellent strength-to-weight ratio, and adds very little weight to the structure.
CLOSED-CELL FOAM STRUCTURE
The Closed-Cell nature of the foam also makes it Water-Resistant. In Exterior Applications like Roofing, only Closed-Cell formulations are used.
ROOF DURABILITY WITH SPF
Roofs insulated with SPF have been lasting well over 30 years in places like the US, where the technology was first implemented on a large scale.
Closed-Cell SPF is not affected by water, and can tolerate a wide range of temperatures (e.g. “RIGIFOAM” installed by THERMAMASTA, is frost- and heat-resistant from -50°C to +100°C).
SPF Material itself is very durable, but it also protects and preserves the Building Components which it covers. Corrosion is prevented (above and below the roof) and Thermal Stress damage eliminated (no more tearing of flashings or sheets rubbing away coatings with movement)
AIR LEAKAGE OF ROOFING
A factor often overlooked by designers and builders, is to stop air leakage in order to maximise energy efficiency.
SPF provides exceptional air leakage control as but one of its additional benefits. This feature has been shown in US studies, to multiply its Insulation Efficiency 3 to 4-fold.
WALKING ON A SPF ROOF
SPF for Roofing is formulated to be capable of withstanding foot traffic (e.g. “RIGIFOAM” installed by THERMAMASTA, has a Density of 45 – 60kg/m3 and a Compression Strength of 0,20 – 0,40N/mm2)
Only if heavier traffic is anticipated (e.g. regular maintenance of roof equipment with heavy tools etc.) is an additional walkway mat applied (various options) on top of the foam, to protect it from excessive impact.
COATINGS OVER SPF ROOFING
If SPF is to be left exposed to sunlight, it needs to be screened with a coat of paint, e.g. a good quality Roof Paint is sufficient to protect the foam. SPF in these exposed situations will last almost indefinitely, as long as the protection coating over it is maintained.
SPF can also be positioned on top of concrete roof slab, and underneath a screed with falls to outlets.
There are numerous ways to approach this, depending on the specific needs of the Client for the project.
THERMAMASTA is available for consultation to plan best options and solutions with the Building Professional and Client. In our experience best solutions can be obtained if details (even practical issues) are discussed at an early planning stage.
SUSTAINABILITY OF SPF ROOFING
THERMAMASTA in association with “RIGIFOAM”, bring Construction Professionals an unparalleled opportunity to meet and exceed the increasing demand for Sustainability, thanks to high performance materials engineered for every Code and Climate.
Example: ‘SPF’ as Sustainable Roofing Solution is unequalled
ASBESTOS ROOFS INSULATED AND PRESERVED WITH SPF
Asbestos roofs can be economically contained and permanently preserved by installing SPF on top.
Roof sheets are cleaned with regulated methods before being seamlessly and permanently coated with SPF.
Inside the sheets can simply be cleaned and coated with an approved coating, to contain asbestos fibres. As the insulation is already taken care of on the outside, there is no need to install ceilings for that purpose, especially in commercial and industrial buildings.
While the SPF acts as high-performance insulation, it also protects the roof sheets from further decay (fibre-cement roofing products eventually need to be replaced, if left un-coated for too long due to decay from thermal shock, moisture cycles, acid rain, microbial attack, etc.)
A common problem with old asbestos roofs, is large gaps which compromise waterproofing. This is also overcome while coating with SPF, as even large gaps are easily and permanently sealed.
By adding SPF on top of the roof, all sheets are bonded together, to greatly increase the structural strength of the sheeting. Roof sheets cannot be individually grabbed, to be vibrated or even ripped off during high wind episodes, which makes the roof much more resilient in storms.
B. TECHNICAL INFORMATION:
B1. THERMAL PERFORMANCE(SPF Material)
- Maximum aged Thermal Conductivity of (‘Lambda’ 0.028 W/(m•K)
- Aged Closed-Cell ‘SPF’ has an average R-value of 0.83 per 25mm thick.
- SPF can provide 100% air leakage control as but one of its additional benefits. This feature has been shown in US studies, to multiply its Insulation Efficiency 3 to 4-fold.
- Seamless SPF coating means no thermal bridging at laps, gaps and joints.
- Self-adhesive means no mechanical fasteners to cause thermal bridging.
R-VALUE ALONE IS NOT THE ANSWER TO ‘REAL-WORLD’ THERMAL INSULATION PERFORMANCE !
B2. SUBSTRATE CONDITIONS
- SPF is self-adhesive onto most clean surfaces
- Only a few require an ‘Adhesion Primer’, e.g. Bitumen waterproofing and ‘fresh’ Galvanised Steel
- During the ‘liquid-state’ the mixed material locks mechanically onto the surface at molecular level, creating an exceptionally strong bond.
- Due to its superior adhesion properties, ‘SPF’ is also specified for Structural enhancement.
- Roofs insulated on the outside with ‘SPF’, have been lasting well over 30 years in the US, where the technology was first implemented on a large scale.
- The product “RIGIFOAM Closed Cell Polyurethane Sprayfoam” which THERMAMASTA install, is frost- and heat-resistant from -50°C to +100°C.
- The Closed-Cell nature of the foam also makes it water-resistant.
- If ‘SPF’ is to be left exposed to sunlight, it needs to be screened with a coat of paint, e.g. a good quality Roof Paint is usually sufficient to protect the foam.’SPF’ in these exposed situations will last almost indefinitely, as long as the protection coating over it is maintained.
- Although classified as a ‘Rigid’ Foam, Closed-Cell ‘SPF’ can accommodate movement of the substrate, sufficient to permanently cover over most construction joints.
- When applied on the exterior of buildings, Thermal Shock is almost completely removed, which results in very low Thermal Movement, only due to varying air-temperature etc.
- Because it seals effectively against vapour, Moisture movement is also substantially reduced.
- Consider the fact that the same material is used to make surfboards, and the amount of flex it needs to endure.
- ” RIGIFOAM” installed by THERMAMASTA contains a Fire-retardant.
- The foam product does not promote flame-spread.
- Will flash initially forming a surface char, and then self-extinguish i.e. does not remain burning when external flame is removed.
- Smoke has similar toxicity as Pine Wood, when it burns. Less toxic than Leather or Felt when it burns.
- For Internal Applications an ‘Ignition/Thermal Barrier’ is recommended, to prevent ‘sporadic flash’ in case of a fire e.g. Gypsum Board; Cementitious Coatings; etc.
B6. WATER PENETRATION
The Closed-Cell Structure makes the foam water-resistant.
Closed-Cell ‘SPF’ is the only insulation approved in the US as “flood-resistant”.
B7. STRUCTURAL ENHANCEMENT
Due to its superior adhesion properties, ‘SPF’ is also specified for Structural enhancement.
Studies in the US indicated that Racking Strength’ of light structures can be increased by as much as 300% by installing ‘SPF’ – effectively bonding all components together.
‘SPF’ has been used to increase the strength of aircraft wings, for its adhesion properties, rigidity, and light weight.
B8. AIR TIGHTNESS
Green Building Handbook Vol 3
Super-Structure and Building Performance
Llewellyn van Wyk, Principal Researcher, Built Environment CSIR
“Air leakage plays a significant role in reducing the thermal performance of the building envelope, particularly in a well insulated building.”
B9. SOUND INSULATION
Closed-Cell ‘SPF’ effectively reduce noise from outside sources by sealing cracks and gaps that allow sound to travel through the walls, floors and ceilings into the building.
Closed-Cell ‘SPF’ generally absorbs more sound from the lower frequencies.
To a degree they are effective against noise caused by vibration, but this is where the Density of the foam plays a bigger role.
An Open-Cell ‘SPF’ version is available for special order which can absorb a wider range of Sound Frequencies, but this can only be used for Internal applications.
‘SPF’ has been thoroughly evaluated by a number of Sustainability Rating Systems overseas (e.g. “LEEDS” in the US) and found to be one of the most Sustainable Insulation Systems to specify today.
Some of the attributes which gives it this excellent rating include:
- Excellent thermal efficiency – leading to optimum energy savings and reduced CO2 emissions.
- Relatively low environmental impact at the building level – the product saves more than 100 times more energy than is used in its manufacture.
- Durability – leading to long term performance and reducing the need for replacement, thereby saving resources and energy over time. It helps to preserve the building components as well, leading to further long-term savings on resources and energy.
- Minimal thickness – minimizing building footprint and land use.
- Additional Benefits – apart from the superior Thermal Insulation, it offers additional benefits which adds value and eliminates need for additional measures e.g. Self-Adhesive; Self-Flashing; Seals Airtight; Vapour Barrier; Enhances Waterproofing; Enhances Structural Strength; etc.
- Transportation – large volumes of material is formed in-situ from compact liquid raw materials, which means no multiple deliveries of bulky materials, or large space for site-storage, required.