Loft Conversions
102 sources in the library on loft conversions. Each one says what the document covers and what it is good for. Name a source to see which document it is and where to read it. One at a time. Page 3 of 3.
- supplier figure RN-CI1C4U
Glazing Vision Ltd
Glazing Vision PitchVent opening roof window for pitched roofs. Two size ranges are published: span 800mm to 1500mm for one variant and 800mm to 3000mm for the other.
- supplier figure RN-Q4TIZY
Glazing Vision Ltd
Glazing Vision SkyHatch roof access rooflight. Manual version: span fixed at 1100mm minimum and maximum. Electric SkyHatch: span 800mm to 1500mm, width 800mm to 2000mm. Minimum upstand pitch 3 degrees, maximum 10 degrees, with at least 5 degrees recommended for standard units.
- supplier figure RN-56MR8S
James Jones & Sons
Site rules for erecting JJI-Joists. Solid timber stability blocks must be a minimum 38 x 125 mm, cut squarely to maintain joist spacing and fastened with a minimum of two 3.35 x 65 mm nails; blocks must be fixed to at least three joists and cover a minimum distance of 1200 mm. Temporary bracing uses 22 x 97 mm continuous longitudinal binders and 22 x 97 mm diagonal braces, with the bracing system at one end of the joist run. Joists must be erected straight and vertical, with maximum deviation from horizontal of 10 mm and from vertical of 2 mm. Loading limit during erection: the weight of material placed on a single joist must not exceed 250 kg, reduced to 200 kg for 195 mm deep joists, and timber bearers are recommended to spread the load. A minimum of 675 mm of cured masonry is required before loading. The guide also sets out the conditions that are not permitted and the service hole rules.
- supplier figure RN-UGYK01
James Jones & Sons
The full JJI-Joist design manual. A JJI-Joist is softwood flanges with a 9 mm OSB/3 web. Four flange widths: A+ 47 mm, B+ 63 mm, C 72 mm, D 97 mm. Standard depths 195, 220, 235, 240, 245, 300, 350, 400 and 450 mm, though 195 mm is A+ only and 350-450 mm are D flange only. Section properties, for example JJI 195 A+: bending moment capacity 5.67 kNm, bending stiffness EI 305.1 x 10^9 Nmm2, shear capacity 10.64 kN, shear stiffness GA 1.234 x 10^6 N, end bearing capacity 8.50 kN on a minimum 45 mm bearing. JJI 245 A+ gives 7.54 kNm and EI 518.0; JJI 300 D gives 17.22 kNm and EI 1899.0 with a 45 mm end bearing capacity of 17.54 kN. Maximum service hole diameters are 75.0 mm in 195 and 220 mm joists, 64.0 mm at 245 mm and 32.0 mm at 400 mm outside the hole charts. Also carries acoustic floor build-ups, fire design charring guidance and thermal performance data.
- supplier figure RN-I1EE5H
Kingspan Insulation
Rigid thermoset phenolic (PF) board to BS EN 13166: 2012 + A2: 2016, faced both sides with a low emissivity composite foil. Declared thermal conductivity 0.019 W/mK. Declared compressive strength 100 kPa to BS EN 826: 2013. Standard board 2.4 m x 1.2 m. BBA Certificate 16/5299 covers thicknesses 25 to 150 mm, made at Pembridge, Herefordshire. Published R-values (m2K/W): 25 mm 1.30, 40 mm 2.10, 50 mm 2.60, 60 mm 3.15, 70 mm 3.65, 75 mm 3.90, 80 mm 4.20, 90 mm 4.70, 100 mm 5.25, 110 mm 5.75. Fire: under System 4 AVCP, K107 has a Euroclass rating of F.
- supplier figure RN-AU8U24
Kingspan Insulation
Fibre-free rigid thermoset polyisocyanurate (PIR) board to BS EN 13165: 2012 + A2: 2016, foil faced both sides. Declared thermal conductivity 0.022 W/mK. Declared compressive stress 120 kPa at 10% compression to BS EN 826. Standard board 2400 x 1200 mm. BBA Certificate 14/5133 covers thicknesses 20 to 150 mm, made at Pembridge and Selby. Published R-values (m2K/W): 25 mm 1.10, 30 mm 1.35, 40 mm 1.80, 50 mm 2.25, 60 mm 2.70, 70 mm 3.15, 75 mm 3.40, 80 mm 3.60, 90 mm 4.05, 100 mm 4.50, 110 mm 5.00, 120 mm 5.45, 125 mm 5.65, 130 mm 5.90, 140 mm 6.35, 150 mm 6.80. Fire: under System 4 AVCP, TP10 has a Euroclass rating of F.
- supplier figure RN-A1M5LJ
Klober Ltd
Three layer air open roof underlay of UK stabilised PP fleece with a meltblown layer, dark blue. Weight 160 g/m2 to EN 1849-2. Water vapour transmission (SD value) EN 12572 0.009 m. Resistance to water penetration EN 1928 W1. Tensile strength MD/CD 280/200 N/50 mm to EN 12311-1; nail tear strength MD/CD 140/130 N to EN 12310-1; elongation MD/CD 50/70% . Fire rating EN 13501-1 EN 11925-2: E. Resistance to temperature -40 C to +80 C. BBA Certificate 07/4435 (cold non-vented and warm non-vented) and NHBC accepted without additional high level ventilation. Suitable for wind zones 1 to 3 with battened headlap and all wind zones with taped headlap at a 345 mm batten gauge.
- supplier figure RN-CHO4HW
Mannok (formerly Quinn Building Products)
Foil faced rigid PIR roof board, 2400 x 1200 mm, thicknesses 20 mm to 200 mm. Thermal conductivity (lambda) 0.022 W/mK. Core water vapour resistivity approximately 300 MNs/gm. Compressive strength greater than 140 kPa. Certified under BBA certificate 07/4444 and IAB certificate 05/0223. Listed applications cover above rafters, above and between rafters, between and below rafters, at ceiling level, loft or attic walls, and cold deck flat roofs. The page does not state a Euroclass reaction to fire classification.
- supplier figure RN-0H8KU0
Marley Ltd
Marley 25mm Eaves Vent System: provides a continuous free vent area of either 10mm or 25mm to the roof void, giving 25,000 mm2 of free ventilation area per linear metre in the 25mm setting. Suitable for roof pitches from 12.5 to 55 degrees, and for both eaves-to-ridge and eaves-to-eaves ventilation, and can also ventilate the batten cavity. Allows clip fixing of all eaves tiles, compresses insulation to maintain airflow, prevents ponding on the underlay and blocks wildlife. Meets BS 5534 requirements and NHBC guidelines.
- supplier figure RN-37SJVQ
Marley Ltd
Marley Universal 10mm Roof Eaves Ventilation System provides a continuous 10mm free vent area to the roof void, sized for lower pitched roofs with deeper insulation. It compresses the insulation at the eaves to preserve airflow, allows clip fixing of all tiles at the eaves, and prevents ponding on the underlay behind the fascia board and wildlife ingress. Meets BS 5534 requirements and NHBC guidelines. Fascia or tilting fillet height must be checked against the tile type and rafter pitch, allowing for the over-fascia ventilator and comb filler strip.
- supplier figure RN-UF16T9
MiTek Industries
Posi-Joist metal web joists. Web types and their clearance between flanges and standard overall depth: PS8 108 mm clearance and 202 mm depth; PS9 131 mm and 225 mm; PS10 159 mm and 253 mm; PS12 210 mm and 304 mm; PS14 279 mm and 373 mm; PS16 327 mm and 421 mm. The open web is sized so MVHR ducting and services pass through the floor zone without notching. Acoustic floor build-ups in the handbook include 202 mm Posi-Joist with 22 mm chipboard and 253 mm Posi-Joist with 18 mm plywood or 22 mm chipboard; ceiling details call for a minimum 35 x 97 C16 noggin nailed to the underside and drywall screws at 230 mm centres for joists 253 mm and deeper. Spans are confirmed through MiTek's interactive span tables rather than a printed table.
- supplier figure RN-CWJY3V
Simpson Strong-Tie
Heavy (H) and light (L) restraint straps in pre-galvanised mild steel, stainless to order. Heavy straps are 4 mm thick and 28 mm wide for lateral restraint of trusses, rafters and joists tied into masonry; light straps are 2 mm thick for vertical loads such as wall plates. Stock lengths 500 to 2000 mm in 50 mm increments, with bend (B) dimensions of 100 mm or 150 mm and twist (T) versions. Characteristic capacity: H series 8 kN using 8 no. N3.75x30 square twist nails into the wall plate; L series 4 kN using 5 no. 5.5 x 50 mm masonry fixings and 3 no. N3.75x30 nails into the joist or rafter. Installation rules given: horizontal lateral restraint straps at not more than 2 m centres, attached to at least three timber members through noggings and packing; the bend must be a minimum 100 mm and positioned at the centre of an uncut block or brick; vertical restraint straps at least 1 m long; masonry fixings are hardened 4 mm x 75 mm nails or 5.5 x 50 mm screws into plugs, with the lowest fixing within 150 mm of the bottom of a vertical strap. Straps fixed to noggings or trusses take eight 3.75 x 30 mm square twist nails evenly distributed.
- supplier figure RN-TL3093
Simpson Strong-Tie
Heavy duty face fix hangers in 2 mm pre-galvanised mild steel, nailed with square twist nails and with bolt holes for 12 mm fasteners into the face. Key installation rule stated on the sheet: the hanger depth must be at least 60% of the carried member depth to prevent rotation unless extra lateral restraint is added at the top of the carried member. Characteristic capacities for C24 timber, R1,k downward with N3.75x30 nails: SAE200 series 7.6 kN into a C16 header and 8.1 kN into a C24 header, using 8 header and 5 joist fasteners, R2,k 4.2 kN; SAE250 12.7 and 13.5 kN with 12 and 7 fasteners, R2,k 5.9 kN; SAE380 18.2 and 19.4 kN with 20 and 10 fasteners, R2,k 8.5 kN; SAE500 33.3 and 35.6 kN with 32 and 16 fasteners, R2,k 12.2 kN; SAE600 42.2 and 45.1 kN with 36 and 20 fasteners, R2,k 15.9 kN. Product dimensions given by joist width from 36-38 mm up to SAEL at 140 and 150 mm, with hanger weights from 0.26 kg to 0.786 kg. Minimum supporting timber thickness with SSH10x40 screws is 47 mm.
- supplier figure RN-MBGE96
Unilin Insulation (formerly Xtratherm)
Width variable pitched roof board with composite foil facers both sides, 1200 x 370 mm, thicknesses 100, 125 and 150 mm. Thermal conductivity 0.023 W/mK. Reaction to fire: Euroclass F. Typical roof U-values to EN ISO 6946 for an unvented sloped roof with rafters at 400 mm centres and a 25 mm void, combined with an under rafter layer: Rafterloc 100 mm gives 0.20 with 30 mm under, 0.18 with 40 mm, 0.16 with 50 mm, 0.15 with 60 mm, 0.14 with 70 mm; 125 mm gives 0.17 to 0.13; 150 mm gives 0.15 to 0.12 W/m2K. An approved vapour permeable membrane is required.
- supplier figure RN-BCR1ZD
Unilin Insulation (formerly Xtratherm)
PIR roof board with composite foil facings both sides, 2400 x 1200 mm. Thicknesses 25, 30, 40, 50, 60, 70, 75, 80, 90, 100, 125 and 150 mm. Thermal conductivity 0.022 W/mK. Compressive strength CS(10Y) 140 kPa. Reaction to fire: Euroclass F. Covered by BBA 23/6997 (2026).
- supplier figure RN-UPXCUK
VELUX Company Ltd
VELUX 3in1 roof window, three sashes in a single opening. Glazing 70 Comfort double glazed: whole-window Uw 1.3 W/(m2K), g-value 0.46, 35 dB. Glazing 66 Well-being triple glazed: Uw 1.0 W/(m2K), g-value 0.44, 37 dB. Roof pitch 15-90 degrees for centre-pivot, solar and top-operated versions, 15-55 degrees for the manual top-hung outward opening version. VELUX recommends a window-to-floor area ratio of 15-20% for roof windows, rising to 25-30% where the window is overshadowed, to reach EN 17037 median daylight.
- supplier figure RN-4JG775
VELUX Company Ltd
VELUX centre-pivot and top-hung roof windows, glazing options quoted as whole-window Uw (not centre-pane Ug). Glazing 70 Comfort double glazed: Uw 1.3 W/(m2K), g-value 0.46, 35 dB sound insulation. Glazing 68 Better Comfort triple glazed: Uw 1.1 W/(m2K), g-value 0.49, 35 dB. Glazing 62 Comfort extra noise reduction triple glazed: Uw 0.92-0.96 W/(m2K), g-value 0.47, 42 dB. Suitable roof pitches 15-90 degrees for centre-pivot, top-operated and solar/electric versions; 15-65 degrees for the electric top-hung outward opening version and 15-55 degrees for the manual top-hung. All glazing includes rain noise reduction, safety laminated inner pane, toughened outer pane and a UV filter.
- supplier figure RN-J4LONE
VELUX Company Ltd
VELUX Heritage conservation roof window, a slim flush-fitting window resembling a traditional cast iron attic window. Glazing 01 Comfort double glazed: whole-window Uw 1.3 W/(m2K), g-value 0.56, 35 dB. Glazing 02 Better Comfort double glazing using advanced vacuum-insulated technology: Uw 1.1 W/(m2K), g-value 0.54, 37 dB. Note the vacuum unit reaches triple-glazing Uw in a double-glazed thickness, which is the point of it for conservation work. VELUX recommends a window-to-floor ratio of 15-20% for roof windows (25-30% where overshadowed) to meet EN 17037 median daylight.
- supplier figure RN-JRH8FF
VELUX Company Ltd
VELUX Low pitch roof window is made for roof pitches of 10-20 degrees, below the 15 degree minimum of the standard centre-pivot range. Glazing 15 Better Comfort triple glazed with glass-to-edge: whole-window Uw 1.1 W/(m2K), g-value 0.50, sound insulation 35 dB. VELUX states a low pitch roof window admits about twice as much daylight as a vertical window of the same size.
- supplier figure RN-PGJ7EI
VELUX Company Ltd
VELUX mini dormer roof window. Glazing 70 Comfort double glazed: whole-window Uw 1.3 W/(m2K), g-value 0.46, 35 dB. Glazing 62 Comfort extra noise reduction triple glazed: Uw 0.92-0.96 W/(m2K), g-value 0.47, 42 dB sound reduction. Roof pitch 15-90 degrees for the top-operated version and 15-55 degrees for the manual top-hung outward opening version.
- supplier figure RN-UW09CY
VELUX Company Ltd
VELUX roof balcony window, which opens to form a balcony. Glazing 66 Well-being triple glazed: whole-window Uw 1.0 W/(m2K), g-value 0.44, sound insulation 37 dB.
- supplier figure RN-6HYJNY
VELUX Company Ltd
VELUX sun tunnel for pitched roofs. Rigid tunnel: 25cm and 35cm diameters, recommended tunnel length 0.9-6m, highly reflective coating giving up to 98% daylight reflectivity; extension tunnel ZTR is recommended where ceiling-to-roof distance exceeds 170cm, taking total length to 600cm. Flexible tunnel: 35cm diameter only, recommended length 1.5m, for use where a beam or other obstruction blocks a straight run. Integrated cover frame suits flat and profiled roof coverings up to 12cm high; not suitable for standing seam metal roofing. Optional low U-value kit ZTB. Ventilation adapter (TWR 0K14 only) has a 10cm pipe connection.