Drywall & Plasterboard Installation

According to EN 14195, metal framing components (tracks, studs, noggings) must comply with specified dimensions, gauge thickness and spacing. Studs are typically spaced at 400 mm or 600 mm centres depending on board thickness and performance requirements. Floor and ceiling tracks must be fixed at maximum 600 mm centres with appropriate fasteners. RRAE/D.L. 96/2008 acoustic requirements may demand specific stud configurations (staggered or resilient channels).

1. Measure stud spacing — must match the design specification (typically 400 mm or 600 mm centres)

2. Verify stud gauge thickness matches EN 14195 requirements for the partition height (0.5 mm for up to 3 m, 0.6 mm for taller)

3. Check that floor and ceiling tracks are fixed at maximum 600 mm centres with correct fasteners for the substrate

4. Confirm noggings are installed at all horizontal board joints, fixture locations and service penetrations

5. Verify that resilient bars or acoustic channels are installed where required by the RRAE acoustic design

- Stud spacing exceeding the maximum, causing board deflection and cracking

- Incorrect gauge thickness for partition height, leading to instability

- Track fixings too far apart or using incorrect fastener types for the substrate

- Missing noggings at board joints and heavy fixture locations

According to EN 520, plasterboard must be fixed with the correct screw type and spacing. Screws must be at least 10 mm from board edges and 15 mm from corners. Maximum screw spacing is typically 300 mm on ceilings and 300 mm on walls at intermediate studs. Boards must be installed with staggered joints between layers in multi-layer systems. The RGEU requires smooth, plumb wall surfaces for habitable rooms.

1. Check screw spacing — maximum 300 mm on ceilings, 300 mm on walls at intermediate studs per manufacturer guidelines

2. Verify screws are set to correct depth — head just below paper surface without breaking through (use depth gauge)

3. Confirm board joints are staggered between layers in multi-layer construction

4. Check that boards are tightly butted at joints without gaps exceeding 3 mm

5. Verify correct board type is used for the application (moisture-resistant in wet areas, fire-rated where required)

6. Ensure boards are not installed with cut edges at external corners

- Screws over-driven, breaking the paper face and losing holding capacity

- Board joints aligned between layers, creating weakness lines

- Standard boards used in wet areas instead of moisture-resistant type (green boards)

- Gaps at board joints too wide for proper taping and jointing

According to EN 13963, jointing compounds and tapes must be compatible with the board type and applied in the correct sequence (typically three coats with sanding between). Joint tape must be fully bedded in compound with no air pockets. Finished surface quality levels (Q1–Q4) should match the intended final decoration as defined by the plasterboard manufacturer guidelines and RGEU requirements.

1. Inspect all joints for visible tape edges, bubbles or ridges — tape must be fully embedded

2. Check that the correct number of jointing coats has been applied (typically 3 coats with progressive feathering)

3. Measure the feathered width of finished joints — should be minimum 250 mm wide for flat joints

4. Verify the surface finish level matches the specified quality (Q2 for standard paint, Q3 for gloss, Q4 for critical lighting)

5. Check all internal and external corners for straight, consistent compound application

- Joint tape lifting or bubbling due to insufficient bedding compound

- Visible joint ridges under raking light, indicating insufficient feathering

- Incorrect finish quality for the intended decoration (e.g. Q2 used under gloss paint)

- Sanding marks visible through thin paint finishes

According to RRAE/D.L. 96/2008, partition walls between dwellings must achieve a minimum airborne sound insulation of DnT,w >= 50 dB. Partitions between habitable rooms and common areas must achieve DnT,w >= 48 dB. Acoustic insulation (mineral wool per EN 13162) must fill the cavity. All gaps and service penetrations must be acoustically sealed to prevent flanking transmission.

1. Verify that acoustic insulation (mineral wool) is installed in the full cavity depth between studs without gaps or compression

2. Check that perimeter tracks have acoustic sealant or resilient strips between the track and the structure

3. Inspect all service penetrations (sockets, switches, pipes) for acoustic sealing — back-boxes should not be aligned on opposite faces

4. Confirm that the partition build-up matches the acoustic test certificate (correct board layers, insulation type and thickness)

5. Where required, verify acoustic performance with on-site testing per ISO 16283-1

- Mineral wool insulation missing from sections of the cavity, creating acoustic weak points

- Back-to-back electrical boxes creating direct sound paths through the partition

- Perimeter tracks without acoustic sealant, allowing flanking transmission via the structure

- Partition build-up not matching the tested configuration (fewer board layers or thinner insulation)

According to EN 520 and EN 13501-2, fire-rated plasterboard partitions must match the tested configuration exactly to achieve the claimed fire resistance (EI 30, EI 60, EI 90 or EI 120). Fire-rated boards (Type F or Type DF per EN 520) must be used. All penetrations must be sealed with intumescent products tested to EN 1366-3. Portuguese SCIE regulations (D.L. 220/2008 and Portaria 1532/2008) define the required fire resistance for each building occupancy type.

1. Verify that fire-rated boards (Type F or DF per EN 520) are used in the correct number of layers as per the fire test certificate

2. Check that all service penetrations are sealed with intumescent collars, wraps or sealant tested to EN 1366-3

3. Confirm that the head-of-wall detail allows for structural movement without breaking the fire seal

4. Verify that joints between fire-rated boards are correctly detailed (taped or backed with steel strips as per test configuration)

5. Check that fire stopping is continuous above suspended ceilings and in concealed voids

- Standard boards used instead of fire-rated Type F boards, invalidating the fire rating

- Service penetrations not fire-stopped, creating paths for fire and smoke spread

- Head-of-wall deflection heads omitted, causing cracking and loss of fire integrity under structural movement

- Fire stopping discontinuous above suspended ceilings

According to EN 520, moisture-resistant plasterboard (Type H per EN 520) must be used in wet areas such as bathrooms and kitchens. The RGEU requires that all wet area walls provide adequate moisture protection. Boards in shower zones must be further protected with a tanking membrane or liquid waterproofing system applied per LNEC ITE 34 and the membrane manufacturer's instructions.

1. Verify that Type H (moisture-resistant) boards are used throughout wet areas — check board colour marking (typically green)

2. Confirm that boards in direct water exposure zones (shower enclosures) have additional tanking or liquid waterproofing applied

3. Check that the bottom edge of boards is held minimum 10 mm above finished floor level to prevent wicking

4. Verify that all cut edges in wet areas are sealed with appropriate primer or waterproofing

5. Inspect ventilation provisions to ensure adequate moisture extraction per RGEU requirements

- Standard boards used in wet areas instead of moisture-resistant Type H

- Tanking membrane missing in shower zones, leading to moisture penetration

- Board bottom edges sitting on the floor slab, wicking moisture upward

- Cut edges left unsealed, allowing moisture ingress into the board core