METAL FRAME WALL INSULATION

Metal frame wall insulation is nothing but a lightweight, fireproof partition wall covered on the inner or outer face of the studs with highly effective insulation such as Rockwool RWA45, RW3, RW5, Knauf RS45, RS60 or RS100. It is primarily used in partition walls or as components in steel frame systems (SFS). In fact, metal stud wall insulation can improve fire safety and sound blocking between spaces in the same property. The majority of commercial buildings use metal stud and track as part of its framing system. Metal stud internal walls offer significantly greater long-term benefits to a building than timber walls. Unlike wood, metal is a material which is not prone to warping or rotting, nor is it vulnerable to mould growth. As a material, metal’s strength doesn’t deteriorate the longer it is used, meaning a building will have efficient, long-term structural integrity. These durable metal wall studs can be used to replace the traditional timber framing, making them both convenient and cost effective. Steel may be a strong, durable framing material, but it’s also a thermal conductor. When not properly insulated, steel allows heat - and associated energy - to travel through the frame. This makes steel buildings particularly susceptible to high energy costs, as well as cold spots and difficulty maintaining temperatures. Insulating the frame and particularly over the frame as well as between the joints stops thermal transfer. This makes the building more comfortable and energy efficient for the occupants. Therefore, it is insulated inside or outside in 90% of cases. Fiberglass batts are the most common type of insulation used in metal stud framing. They're easy to install and relatively inexpensive. A partition insulation such as RWA45 Rockwool Acoustic Insulation Slab or Celotex or Kingspan solid rigid boards are also used for this type of construction. It should be emphasized that these are usually high-density products that guarantee soundproofing (>45kg/m3). It is recommended to use 60kg/m³ slabs as they offer the best sound insulation for the money spent. Although, those slabs still have higher density than other forms of insulation unlike thermal insulation which is lower in density and supplied in rolls. Unlike rolls, slabs are normally for walls. However, these high density insulation may weigh more than 100kg/m3. For instance, an average square office measuring 16'x 16' may call for 5.2m3 of acoustic insulation, therefore an extra weight of 520kg (half a ton). This may be worth considering when few offices are built on a single storey. Therefore, the most commonly used material for insulating interior walls is light mineral wool. It comes in the form of roll measuring usually 10000mm x 600mm, offering high level of sound absorption, noise reduction, better thermal and fire performance in internal wall partitions. Rolls are rot proof, non-hygroscopic, do not sustain vermin and will not encourage the growth of fungi, mould or bacteria. The absence of air gaps is crucial to achieving a high level of performance in the relevant application. Acoustic partition rolls adapt to any slight imperfections in the substrate and knit together, eliminating any air gaps (thermal bridging). In fact, roll is particularly effective at preventing the hollow sound that can occur in partitions with unfilled cavities.

METAL FRAME INSULATION SIZES

The spacing of the structure is strictly related to the dimensions of the gypsum board, i.e. 1200x2400.  Generally speaking, studs should be placed at every 400 or 600mm. However, the industry standard of metal frame centre spacing is 600mm. Possibly for the reasons you should be looking for insulation with this particular width. However other 400mm centre spacing is also used in the UK. The only advantage for 400mm is a stronger structure otherwise is it better to have 600 mm centres.

• 600mm, more insulation, less thermal bridging, less metal studs, 600mm - living spaces and bedrooms
• 400mm, less insulation, more thermal bridging, stronger structure, 400mm - utility, kitchen or bathrooms

Rockwool RWA, RW, Knauf RS or Terrawool TW range offer boards size  1200mm x 600mm, which makes them ideal for insulation of this type of structure. On the other hand rigid insulation boards such as Celotex, Xtratherm or Kingspan come standard size 2400mm x 1200mm. They can be easily cut to 2 x 600mm or 3 x 400mm widths to fit between studs. These high performance PIR insulation boards are designed for internal wall insulation applications and can help achieve excellent U-values with both sides faced with low emissivity composite foil facing. Either way, installing insulation boards will provide excellent thermal performance and appropriate fire resistance within the wall cavity.

FITTING METAL FRAME INSULATION 

Start at the bottom and gently place the insulation between the metal studs. Work up the front of the insulation toward the top. Confirm that the insulation completely fills the cavity between studs. If installing paper or foil-faced insulation, make sure the facing is toward the interior of the home. Cut the insulation with the utility knife when installing around utility lines, plumbing or any kind of cabling, if necessary. Cut the insulation boards accurately to ensure they will fit tightly around openings such as window and door openings. Fit the insulation boards to the external face of the steel studs, butted tightly together to ensure a continuous layer of insulation, ensuring vertical board joints coincide with a vertical steelwork member. Make sure the insulation sits between the obstruction and fill any gaps between the insulation and the metal framing with expanding polyurethane foam to avoid thermal bridging issues. Repeat the process to completely install all the insulation between the metal studs.

METAL FRAME WALL INSULATION PRICES

If you are looking to insulate a 100mm thick stud wall, you should expect to pay anything from £3.46 to £40 per m2. While fibreglass insulation is the cheapest available option costing a little as £3.46 per m2, it does not perform as good as Knauf RS or Rockwool RW range. For instance 100mm Knauf RS45 (45kg/m3) cost as of 2022 £11.46 per m2. On the other hand, its highest density grade (100kg/m3) cost £20.24. If you are about insulate a partition wall on the outer face of the studs, using 52.5mm thick insulated plasterboard such as Kingspan Kooltherm K118 or Xtratherm XT/TL-MF you would be paying as of 2022 £29.91 per m2. Filling steel stud wall with Celotex PIR rigid insulation board would cost not more than £18.55 per m2. The costs given here are given in good faith as an indicative guide only and should be used with understanding. Insulationgo Limited cannot accept any liability for any budget produced using these figures.

METAL FRAME  INSULATION PRODUCTS

• Knauf RS45
• Knauf RS60
• Knauf RS100
• Knauf Rocksilk Flexible Insulation Slab Multi-purpose
• Knauf Foil Faced Two Sides RS45/RS60/RS100 
• Knauf Acoustic Insulation Roll Earthwool APR
• Rockwool RWA45
• Rockwool RW3
• Rockwool RW5
• Rockwool RW6
• Rockwool Steel Frame Slab
• Rockwool FLEXI®
• Kingspan Kooltherm K118 Insulated Plasterboard
• Kingspan Thermawall TW55/TF70/TP10 PIR Wall Insulation Board
• SR/TB-MF Xtratherm Safe-R Thermal Insulated Plasterboard
• SR/FB Framing Board Xtratherm Safe-R Insulation
• XO/FB Xtratherm Xtroliner Framing Board
• Gyproc Thermaline PIR Insulated Plasterboard
• Knauf EPS Thermal Laminate Insulation Board
• Gyproc Thermaline Basic Insulated Plasterboard
• Superglass Multi Acoustic Partition Roll Insulation
• IKO Enertherm ALU PIR Rigid Insulation Wall Board
• Celotex TB4000 PIR Rigid Insulation Wall Board
• Xtratherm Thin-R PIR Rigid Insulation Wall Board
• Recticel Eurothane GP PIR Insulation Wall Board
• EcoTherm EcoVersal PIR Insulation Wall Board
• Terrawool TW50 Acoustic Insulation Slab
• URSA 10 Diverso Insulation Roll
• Knauf Earthwool Insulation Roll 44 Combi Cut 
• URSA Acoustic Insulation Roll Glasswool
• Knauf Earthwool Acoustic Insulation Roll APR
• 12.5mm Knauf Sound Panel Acoustic Plasterboard ǀ Sound Shield TE

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Video credit:https://www.youtube.com/watch?v=bDt_MDTEHlw