Before you call
The Historic Roof Assessment Checklist
A 31-point checklist for owners and church boards assessing a historic slate or clay tile roof. The first of its six sections is open below. Enter your name and email to unlock the other five sections.
Your details go to Justen only. Privacy notice.
The checklist
1 of 6 Records and history
- Note the roof's original material and the decade it was installed.
- List every prior repair, reroof, or patch you know about, with rough dates for each.
- Pull any permits filed for past roof work, and any insurance claims tied to the roof.
- Confirm whether the building holds landmark or historic district status, and name the body that must approve new roof work.
- Gather original drawings, tile or slate invoices, and manufacturer records still on file.
That is 1 of 6 sections. Enter your name and email above to unlock the other five and the print version on this page.
From the ground, with binoculars
- Scan every roof plane for missing, slipped, or cracked slates or tiles.
- Check the ridge and hip lines for straightness and any sign of movement.
- Look for sagging or wavy roof lines between rafters or trusses.
- Trace any staining patterns back to a valley, chimney, or dormer.
- Note the compass direction of each roof plane. Wear rarely spreads evenly.
Flashings and metalwork
- Check valley flashing for rust, splits, or debris buildup.
- Inspect chimney flashing for gaps, lifted edges, or loose counter-flashing.
- Look at dormer flashing and step flashing along every sidewall.
- Check gutters and downspouts for rust, sagging, or pulling away from the fascia.
- Note any tar or caulk patched over metal flashing. That is a repair covering a bigger problem.
Attic and interior
- Go into the attic in daylight and look for light coming through the deck.
- Check the underside of the roof deck for water stains, dark streaks, or soft spots.
- Note the condition of the deck boards, including any sagging or rot.
- Check attic ventilation. Look for soffit, ridge, or gable vents, and whether they are blocked.
- Look at fasteners and framing hardware visible from inside for rust or corrosion.
Slate and clay tile specifics
- Look for delamination or powdering on the slate surface.
- Check for nail sickness, where failed fasteners have let slates slide.
- Note the quarry or color of the existing slate, for matching replacement stock.
- Record the tile profile and any manufacturer marks stamped on the underside.
- Check for broken interlocks between tiles.
- Look at the mortar bedding at ridges and hips for cracking or loss.
Safety and scope
- Do not walk on slate or clay tile roofing. It breaks underfoot and the damage is often invisible until it fails.
- If the roof has suspected asbestos containing underlayment or cement products, have it tested by a licensed lab before anything is disturbed.
- Photograph everything, and note the date on each photo.
- Have square footage, roof age, and any known repair history ready for the site visit.
- List access points and safety concerns already known, like a locked attic hatch or a fragile parapet.
Bring this to the site visit. It shortens the survey and sharpens the scope.
Ready for eyes on the roof?
Justen usually calls back within one business day. Then a site visit and a written scope.