All guides
Concrete admixtures: plasticisers, retarders and accelerators under ASTM C494 — what they do and when to use them
Chemical admixtures are added to concrete in small doses and change its behaviour: they cut water, delay or speed up setting, or make it self-compacting. The seven types in ASTM C494, what the standard requires, and when they help in the Saudi heat.
Concrete bonding agents: the type you let dry and the type you must place onto wet — ASTM C1059
When placing new concrete or render over old concrete, a bonding agent improves adhesion. But the wrong type used the wrong way can act as a bond breaker. The two types in ASTM C1059, and the difference between acrylic, PVA and EVA.
Concrete repair: R1 to R4 repair mortars under EN 1504, and when a repair is structural
Spalling concrete cover and exposed rusty steel are among the most common problems in older and coastal buildings. The European EN 1504 system for protecting and repairing concrete, the R1–R4 repair mortar classes, and why surface patching is not enough.
Roof waterproofing: bitumen membranes, single-ply membranes and liquid-applied systems — compared with pros and cons
Roof leaks are among the most common home problems. A comparison of flat-roof waterproofing membranes: SBS and APP modified bitumen, TPO, PVC and EPDM single-ply, liquid-applied systems and spray foam — and where the thermal insulation goes.
Joint sealants: how to read an ASTM C920 classification and choose between silicone and polyurethane
Movement joints in tiling, around windows and in facades need a flexible material that tolerates movement. ASTM C920 classifies sealants by type, grade, class and use. What the codes mean and how to choose.