Drift: Roof Snow Load Calc — Support
Need help?
Email roman.kopaliani@gmail.com with your question. Please include:
- What you were trying to do
- What happened instead
- The app version (Drift → More → About)
Frequently asked
What's free and what's in Drift Pro?
Free forever: the Roof Load Check (including verdicts against FEMA's danger band) and Roof Safe. Drift Pro ($6.99, one-time) unlocks the Storm Planner, Drift Watch, and Ice Dam Check. No subscription.
How much snow can my roof hold?
Honestly: no app knows — capacity depends on your rafters, spans, code year, and condition. What Drift does is estimate the load that's up there using FEMA's published equivalences (a foot of fresh snow ≈ 5 psf; 3–5 inches of packed snow ≈ the same 5 psf; an inch of ice ≈ a foot of fresh snow) and compare it to FEMA's 20–25 psf danger discussion for typical roofs. When the estimate approaches the band — or any warning sign appears — the answer is a roof rake from the ground or a structural engineer.
Why won't Drift just tell me my roof is fine?
Because it can't know that, and pretending otherwise would be dangerous. The no-"safe" rule is enforced by an automated test in Drift's code. Estimates against published figures, warning signs that always override numbers, and honest escalation — that's the whole design.
What are the warning signs?
Per FEMA: sagging ceilings or ridge lines, new creaking or popping sounds, doors and windows that suddenly stick, cracks opening in drywall, sagging sprinkler lines or ceiling grids. Any of these under snow load: get people out first, then call a structural engineer.
Should I climb up and shovel the roof?
No. Use a roof rake from the ground, working from the eave upward in layers. Climbing a snow-loaded roof adds your weight as a point load exactly where it's least welcome, on a surface built for falling off.
Do heat cables fix ice dams?
They treat the symptom. Ice dams form because attic heat melts roof snow that refreezes at the cold eave — the lasting fix is air-sealing the attic floor and insulating to your zone's target, which is the same work that cuts your heating bill.