A solar array is a grid of holes in a post-tensioned deck. Clear every one first.

Solar racking and rooftop equipment mean drilling a grid of anchor penetrations into a structural concrete deck — and those decks, on towers, podiums, and parkades, are very often post-tensioned. A single anchor into a post-tension tendon is a serious safety event and a $20,000–$75,000+ repair; into a conduit it's an outage. GPR scanning clears every anchor location first, so the array goes down on schedule, the anchors hold, and the structure stays intact. It also protects the deck's waterproofing strategy by keeping penetrations where they belong.

Frequently, yes — post-tensioned slabs have been standard in BC towers, podiums, and parkade decks since the early 1970s, and a roof or amenity deck over occupied space is often exactly that. That's precisely why blind anchoring into these decks is so dangerous: the tendons are stressed to 15–20 tonnes each and follow a draped profile you can't see from the surface. We map that drape and mark keep-clear zones before any rack foot or equipment anchor is drilled.

Yes — solar and equipment anchoring is high-volume drilling, so we scan it as a batch. A day rate clears the full anchor grid in one mobilisation, with each foot location marked clear or shifted to miss reinforcement while preserving the layout's structural and edge-distance requirements. That's far more cost-effective than per-anchor callouts, and it keeps the install crew moving across the deck without aborted holes.

Rooftop and parkade decks carry conduit, drainage, and sometimes radiant or snow-melt lines embedded in or under the slab. GPR distinguishes these from reinforcement and marks them, so an anchor penetration doesn't cut a live conduit or breach an embedded line. For decks with radiant or hydronic embeds the scan is especially valuable — those lines are expensive and disruptive to hit.

Indirectly but importantly — by confirming exactly where anchors can go, scanning keeps penetrations to the planned, properly-flashed locations instead of forcing field relocations that compromise the membrane. On podium and amenity decks over occupied space, where a botched penetration becomes a leak into the suites below, knowing the clear anchor points before drilling protects both the structure and the waterproofing. Pair with our envelope and deck investigation services where membrane integrity is in question.

When required, an annotated record of cleared anchor locations against the reinforcement and embed map — the deliverable a structural engineer or solar EPC often conditions the penetration permit on. It's quoted up front as part of the scope. Routine clearance, though, is same-visit scan-and-mark so the install proceeds without delay.