If you have a basement or cellar beneath your house that you can get into safely, take a look down there to see what type of floor you have. As this requires fitting insulation above the rafters the roof covering will have to be removed in order to fit the insulation. They are needed to help ventilate the space under your floor and stop your floorboards rotting. According to the schedule method of calculation R-values in NZS 4218, the floor R-value minimum requirement for all climate zones and wall types is R1.3. Insulation is laid on the concrete and covered with a screed. The graphic shows an example of a slab on grade that is structurally and thermally isolated from the perimeter foundation wall. Under Slab insulation is a fundamental part of the building envelope to comply with the National Construction Code (NCC) section J for commercial buildings. R-10 radiant slab insulation is required for all compliance paths. If the foundation is on frost-susceptible soils, install a layer of impermeable insulation horizontally in the soil at a slope ratio of 1:5 for at least 1 m (3 ft.). Intermediate (separating) floors – floor in between levels where insulation needs to be adaptable to fit in-between floor-joists. It is the ideal material to stop energy loss at the foundation slab. CLIMATE ZONE. In the average home, approximately 10% of the heat loss is through the ground floor. Floor insulation - Designing Buildings Wiki - Share your construction industry knowledge. Insulation at the vertical slab edge and under the slab perimeter provides this bond break. The side-by-side insulation comparison highlighted previously found the EPS retained 94% of its specified R-value, while the XPS lost nearly half of its insulating capability over the 15 years the materials were on the foundation. Sign up for a … Below-Grade Under Slab with FOAMULAR® XPS insulation. • Insulation requirements for slab on grade floors is further specified in IECC section 402.2.8. However, it may also be provided in upper-floors between heated and unheated areas. From 1 July 2019 all other rented homes covered by the RTA must also meet the insulation requirements. 50% of required insulation. Exterior insulation to the footing and insulation under all heated slab areas. Easy Installation. A 20mm thick piece of insulation is fixed to the perimeter (external) walls, to a height to include the depth of floor insulation and screed. Heated Slabs • 2015 IECC • 2018 IECC. Moisture resistance is also important for belowgrade and under-slab insulation, since wet products provide much lower thermal resistance. Take our online course on the Building Regulations and Standards. Moisture Management. This reason by itself can justify the use of under-slab insulation. Table C402.1.3 Envelope Insulation Minimum Requirements. Insulation requirements for slab-on-grade floors can be found in section R402.2.9 of the 2012 IECC and 2015 IECC, as well as section N1102.2.9 of the 2012 IRC and 2015 IRC. R-5 shall be added to the required slab edge R-values for heated slabs. In this application, the loads are transmitted from the building through the thermal insulation into the soil. Current building codes vary by region and state, but what is consistent is that if you insulate to the minimum requirements of code, your basement will still account for a significant and unnecessary portion of the heat loss in your home. Unitherm® is made from Unipoly®, a light-weight moulded polystyrene material with exceptional thermal insulation properties. Insulation can be laid over the existing floor, but if a floor is being replaced, this is a perfect opportunity to improve the standard of insulation. Namely, if you are only digging the slab, you will need to take into account the thickness of the insulation, since it will affect the depth of the slab. Many well-organised and skilled builders prefer to opt for insulation beneath a floated concrete slab, as this eliminates the need for a secondary floor screed. requirements. Insulation under slab products are provided with facings that are designed to be specific for individual under slab applications and are explained in more detail below. a) Slab on grade at foundation wall with exterior insulation to the footing. As you can see below, there are separate regulations for England, Wales and Scotland. The guidance now states that ”a minimum RSI 0.88 (R-5) under-slab insulation is in compliance when installed for a heated floor in contact with the ground where the floor is fully below frost line,” and that ”a minimum RSI 1.32 (R 7.5) under-slab insulation is in compliance when installed for a heated floor in contact with the ground where the floor is above the frost line.” Insulation is applied to houses with slab-on-grade foundations exactly as you would insulate the outside of a full basement (see Section 6.1, Insulating the basement from the outside). The NCC requirements for wall and ceiling linings (which include under (suspended) slab insulation) are prescriptive and outline the minimum performance a product must achieve in order to comply. 4 Key Attributes: Durability. Load-bearing thermal insulation under foundation slabs is beneficial with regard to energy saving and specifically in the prevention of thermal bridges. b) Slab on grade at foundation wall with interior insulation down 1.2 m, or to the footing with a thermal break at the slab. Therefore, insulation as a means of reducing heat loss is typically installed on the ground floor. For passive design, achieving a higher R-value is recommended - using R1.9 (this is the minimum R-value required for a heated floor) as the minimum is recommended. The first important thing to pay intention to is the depth of the floor slab. Insulation under the slab can reduce temperature swings in the heated space and respond quicker to new changes in thermostat settings. In fact, where this is the case, upgrading your floor insulation is required in order to comply with Building Regulations. This suggests that insulating slab edges is far more effective for preventing heat loss than insulating the underside of the slab. Above grade insulation shall be protected. Unitherm® exceeds ASTM C578, must meet the minimum insulation requirements. Determining How Much Insulation. There will be a damp-proof membrane under the insulation and possibly a second membrane on top, depending on the type of screed. The most common concrete floor system consists of a sub-soil layer, 4 to 6 inches of gravel, a reflective insulation material, and a 3 to 4 inch thick concrete slab that often incorporates radiant heating tubes. Below that, there are more detailed guides to the thermal insulation parts of Building Regulations / Standards. This guidance provides a simple visual test for landlords and tenants to check the condition of existing insulation materials which are likely to be found in roof spaces and under suspended floors. It can be used under the ground floor slab directly placed on the ground, it can be fixed underneath a basement or car park soffit with visual requirements – or below an intermediate floor with a separate ceiling finish. Insulation above a concrete floor is generally associated with suspended pre-cast construction, such as concrete beam and block systems. The math is pretty simple – the thicker the concrete floor insulation material – the deeper the slab … Typically, you might need around 150mm of EPS insulation for a below-slab setup, while an above-slab set up could be 100mm of PIR – but the exact depth will depend on the energy efficiency level you’re aiming for. All other. insulation integrity. Under Slab insulation is a fundamental part of the building envelope to comply with the National Construction Code (NCC) section J for commercial buildings. The slab is made from concrete which is poured on prepared and compacted earth and then reinforced for durability and longevity. How would that be? Code requirements for slab insulation are very poorly written; in fact, they are almost unintelligible. Performance Attributes. ROCKWOOL insulation can be applied under a concrete slab/floor for different purposes. Code requirements. Where the slab on grade is in contact with the ground, the minimum thermal resistance (R-value) of the insulation around the perimeter of unheated or heated slab-on-grade floors designed in accordance with the R-value method of Section C402.1.3 shall be as specified in Table C402.1.3.The insulation shall be placed on the outside of the foundation or on the inside of the foundation wall. Whilst the edging insulation may be on show, it is covered by wall plastering and skirting boards. 502.1.4.10 Below Grade Walls: Below grade exterior wall insulation used on the exterior (cold) side of the wall shall extend from the top of the below grade wall to the top of the footing and shall be approved for below grade use. A concrete slab (or suspended beam and block construction) is laid over a damp proof membrane. Interior wall insulation and insulation under all heated slab areas. Insulation Placement for Heated Slabs Windows, Doors and Skylights (9.36.2.7.) Forklifts to be used in the building impart 8,000 pounds of force at the wheel, which has a 6-inch by 10-inch tire footprint on the slab. Insulation can be installed above an in-situ concrete floor as long as the dpm is placed above the structural slab to reduce the risk of damage to moisture sensitive floorings. EPS insulation in an under-slab application Take the case of a warehouse with a 6-inch-thick, 2,500-psi concrete slab on 2 inches of EPS insulation with a rated stiffness of 360 psi for one inch. h. R-15 for 36” below + R-5 full slab; R-15 for 36” below + R-5 full slab; 2018 IECC Table C402.1.4 Opaque Thermal Envelope ; Opaque doors. Specification C1.10 (section 4) of the Building Code of Australia Vol 1 2019 (BCA) contains wording as follows:8 Wall and ceiling linings: Group R; Heated slabs. R-15 for 36” below; R-15 for 36” below. Limited Warranty. 5 AND MARINE 4. Here’s my translation: This article is only available to GBA Prime Members. Under Slab – ground floor or basement floor in direct contact with the ground, susceptible to losing heat, requiring robust insulation to improve thermal performance. Unitherm® is a cost-effective, durable and energy efficient solution for insulation applications. The construction build up for this can be seen on our online U-value calculator. If it was terribly inefficient to run without the insulation under the slab, that would mean soil under the slab would be colder than the slab itself. Under slab insulation improves the thermal efficiency of the property by adding thermal resistance to the underside of the concrete slab on which the property is built. Get all the construction documentation you'll need, in a single click: Specify This Solution ZIP | 4.8 MB. Cold Pitched Roof . Determining under-slab insulation requirements. This means that the decisive criterion in the selection of thermal insulation quality is the existing pressure load. the insulation under the slab or by increasing the thickness of the insulation under the slab (see Build 109, pages 28–29). ASHRAE 90.1 Compliant. Heated slabs. Effective R-Value - Thermal insulation requirements are now defined in terms of effective insulation ... thermal break along edge of slab with a min. The RPA Guidelines provide a simple formula for calculating the R-value for heated slab insulation. Where the heating is likely to be turned on and off, such as in new-build domestic properties, and a faster thermal response is required, the ‘floating floor’ arrangement of insulation above the slab can be more appropriate. 10. If the floor is a suspended wooden floor, you will probably be able to see wooden joists and the undersides of the floorboards. All window, door and skylight assemblies have labeling . • Special Insulation exceptions related to ceilings with attic spaces, ceilings without attic spaces, masonry veneer and thermally isolated sunrooms are set forth in IECC section 402. Heat can be transferred to the earth, which limits temperature control inside the property. This roof type will require a breathable membrane, like Kingspan nilvent, to be fitted above the insulation. Insulation below the slab suits continuous, low level heating, gradually warming the thermal mass of the concrete and sustaining it at a consistent temperature. I'm speaking about the long run of maintaining a slab temp constantly at 35 degrees over the course of a winter.