Valleys are where shingle roofs leak first. Two slopes' worth of water, one narrow channel, and any weakness shows up as a ceiling stain — usually 6 months after the actual failure started. Underlayment probe, debris-dam audit, and metal-fatigue survey for every valley on your roof.
Valley type identification (open metal, closed-cut, woven) per valley
Underlayment probe at valley edges — ice-and-water or standard felt
Metal fatigue, corrosion, and fastener audit (open metal valleys)
Cut-shingle alignment and sealant condition scoring (closed-cut)
Debris dam mapping and damage-vs-maintenance scoring
Written scope: valley clean, re-metal, or re-line with ice-and-water
Full walk of every accessible valley on your roof. Valley type identification per valley — most homes have a mix. Open metal audit: gauge check, coating condition, edge sealant, fastener count, hem integrity. Closed-cut audit: shingle cut-line alignment, cut-edge sealant, uphill overlap scoring. Woven audit: interweave integrity, hump/crease damage, replace-recommendation reasoning. Underlayment probe at valley edges to determine what's underneath (ice-and-water, synthetic, 15# felt). Debris dam photo mapping per valley with maintenance-vs-damage scoring. Written scope with per-valley recommendation: clean, re-flash, or full valley rebuild.
NM homeowners with visible ceiling stains that don't correlate to obvious roof damage. Owners with multiple valleys and lots of tree cover (needles, leaves, cottonwood fluff). Buyers under contract on complex-roofline homes (lots of dormers, hips, or additions). Owners with older woven valleys wanting a replace-vs-leave scoping. Owners planning a re-roof who want the valley scope specified before bidding.
Verbal Walk — $149 Standard Valley Report — $299 Detailed w/ Per-Valley Photos + Written Scope — $449 Bundle with Full Shingle Report — $199 add-on Most valley inspections are $299–$449. Catching a debris-dam-caused underlayment failure before it soaks the deck saves $2,000–$4,000 in interior + framing repair.
Because valleys concentrate water — a valley collecting two 15-foot slopes handles 4x the water of the field. Any weakness (short underlayment lap, unsealed metal edge, debris dam, cut shingle mis-alignment) shows up there first. Most 'ceiling stain' calls I take trace back to a valley problem.
Open metal (24-gauge painted steel or aluminum, ice-and-water underlayment beneath) is what I recommend for NM's hail + UV combo. Closed-cut is fine on architectural shingles under 10 years old but fails faster. Woven is legacy and should be phased out on any re-roof — I score which type you have and flag if it's the wrong choice for your exposure.
No — debris dams are how valleys fail. Piled leaves, needles, and gravel hold water against the shingle for days, degrading the sealant and forcing water sideways under the courses. I photograph every debris dam and score it as maintenance-only or already-caused-damage before it becomes a $2,000 interior repair.
Cap metal + crack map.
Per-unit re-flash scoring.
Factory & warehouse membrane + equipment audit.
Multi-family portfolio pricing and capital plans.
I've watched too many neighbors sign contracts they didn't understand for roofs they didn't need. That stops with a written report they own.