Real Roof
Case Studies
These are actual treatment records from properties we've serviced on Vancouver Island. Each case documents initial conditions, treatment protocol, and observations at 6 weeks, 6 months, 24 months, and 3 years post-treatment.
No stock photos. No composite scores. Observations recorded by the same technician at each visit.
Architectural asphalt shingle — 3-tab, installed 2009
North-facing primary slope, moderate Douglas fir canopy
Outcome Summary
- Roof Life Extended
- 7 years
- Replacement Cost Avoided
- $22,000
- Treatment Cost
- $680
- ROI
- 3,135%
- Warranty Status
- Active — no retreatment required at 3-year mark
Initial Condition at Inspection
Stage 3 colonisation. Full black streaking from Gloeocapsa Magma across 85% of north slope. Active moss growth on all four rake edges, 2–4 cm thick mat at ridge line. Granule loss visible in downspout sediment. Shingle edges beginning to lift at northeast corner.
Oak Bay — architectural asphalt shingle, north-facing slope
Property photograph — Vancouver Island.
Treatment Protocol
Soft wash biocide application at 3% sodium hypochlorite concentration with surfactant. Zero-pressure roof walk. 25-minute dwell time. No rinse — rain-activated residual.
Documented Timeline
Pre / Day 0
Treatment Day
Application Complete
- Roof visually unchanged immediately post-treatment — expected and intentional
- Moss coloration unchanged (green). Biocide requires 2–4 weeks to penetrate cell walls
- No granule disturbance observed. No shingle lifting during walk
- Downspout guards installed to capture moss debris during die-off phase
Die-Off Active
6 Weeks Post-Treatment
Active Die-Off Phase
- Moss turned brown/orange across 100% of treated area — confirms successful penetration
- Gloeocapsa Magma colonies beginning to lighten (grey → brown) as UV protection degrades
- Loose moss mat detaching at ridge line and washing into gutters with November rain
- Rhizoid root systems confirmed dead — pull test shows zero anchoring strength
Clearing
6 Months Post-Treatment
Surface Clearing
- 90% of dead moss physically gone — carried off by 6 weeks of rain and wind
- Black streaks fading from dark charcoal to mid-grey. 40% lighter than treatment day
- Shingle granule surface now visible across north slope for first time since approx. 2017
- Lifted northeast corner shingles have re-seated — moisture evacuation restored
- No new moss protonemata (regrowth threads) visible under close inspection
Clean
24 Months Post-Treatment
Clean — Monitoring Phase
- North slope fully cleared of Gloeocapsa streaking — shingles returned to original charcoal tone
- Zero active moss growth. Minor lichen spore presence at north rake (expected for zone)
- Granule integrity confirmed — no accelerated loss since biocide treatment
- Shingle flexibility test: no cracking or brittleness. Lifecycle estimate revised upward by 5–7 years
- Gutters clear. No biological sediment in downspouts
Protected
3 Years Post-Treatment
Warranty Assessment
- Roof remains free of moss growth — warranty intact, no retreatment required
- Light Gloeocapsa spore activity detected on north ridge (Stage 1, pre-colonisation)
- Soft wash preventative retreatment recommended within 6–12 months to maintain protection
- Estimated roof remaining life extended from 4 years to 11 years through treatment vs. replacement path
- Owner decision: scheduled maintenance retreatment booked for spring 2025
Cedar shake — original to 1962 construction
West-facing, mature oak canopy on two sides
Outcome Summary
- Roof Life Extended
- 12 years
- Replacement Cost Avoided
- $31,000
- Treatment Cost
- $520
- ROI
- 5,862%
- Warranty Status
- Active — 2-year warranty satisfied. Pre-sale inspection passed.
Initial Condition at Inspection
Stage 4 colonisation on west slope. Cedar shakes saturated — surface moisture retention even in dry August. Extensive moss mat 5–8 cm thick. Multiple shakes split along the grain from freeze-thaw moss penetration. Inspector flagged as material defect in 2022 pre-sale report.
Saanich — cedar shake heritage roof, west-facing with mature canopy
Property photograph — Vancouver Island.
Treatment Protocol
Heritage cedar protocol: diluted biocide at 1.5% sodium hypochlorite (lower concentration to protect cedar tannins). Extended 45-minute dwell. No mechanical contact. Post-treatment zinc strip installation at ridge to provide ongoing protection via rainwater mineral wash.
Documented Timeline
Pre / Day 0
Treatment Day
Pre-Treatment Assessment
- Pre-treatment moisture meter reading: 28–34% across west slope (dry cedar should read 12–15%)
- Heritage protocol selected — standard concentration would bleach aged cedar
- Zinc oxide ridge strip fitted — passive release lasts 10–15 years
- Split shakes documented: 6 individual shakes on west slope requiring replacement
Die-Off Active
8 Weeks Post-Treatment
Die-Off Confirmed
- Moss mat entirely brown and desiccating — cell structure destroyed
- Cedar surface beginning to show through thinning moss layer at peak zones
- No bleaching or colour change to cedar shake observed — dilute protocol confirmed correct
- Zinc strip producing visible white calcium carbonate wash down centre of ridge
Clearing
6 Months Post-Treatment
Cedar Surface Restored
- Moss fully shed. Cedar grain surface visible across 95% of west slope
- Moisture meter now reading 13–16% — within acceptable range for aged cedar
- Cedar natural silver-grey weathering tone uniform and undamaged
- 6 split shakes replaced by owner (pre-identified at treatment day). Balance of shakes structurally sound
Clean
24 Months Post-Treatment
Cedar Healthy — Zinc Active
- Zero moss regrowth. Zinc strip wash clearly inhibiting spore adhesion on ridge and upper 40% of slope
- Lower slope (beyond zinc wash reach) showing Stage 1 spore activity — within expected parameters
- Cedar flexibility and grain integrity confirmed good — no new splits since treatment
- Pre-sale inspection (home listed Oct 2023): roof passed — defect flag removed from 2022 report
3-tab asphalt shingle — 2004–2007 construction
Mixed — two north-facing, one south-facing
Outcome Summary
- Roof Life Extended
- 5–8 years per property
- Replacement Cost Avoided
- $54,000 across portfolio
- Treatment Cost
- $1,620
- ROI
- 3,233%
- Warranty Status
- Active on all three properties
Initial Condition at Inspection
Portfolio of three rental properties on the same street. All three at Stage 2–3 colonisation. Tenant complaints about staining and gutter blockages. Property manager flagged all three in same annual inspection cycle.
Langford — 3-tab asphalt shingle, rental portfolio property
Property photograph — Vancouver Island.
Treatment Protocol
Multi-property package treatment. Sequential same-day service: all three properties treated within 8 hours. Standard soft wash protocol at 3% concentration. Volume pricing applied.
Documented Timeline
Pre / Day 0
Treatment Day
Three Properties, One Day
- Property 1 (north-facing): Heavy Stage 3 — full black streaking, active moss at all four ridges
- Property 2 (north-facing): Stage 2–3 — moderate streaking, moss mat 1–3 cm at ridges
- Property 3 (south-facing): Stage 2 — light streaking, early moss at north rake only
- All gutters cleared before treatment. Downspout guards installed on Properties 1 and 2
Clearing
6 Months Post-Treatment
All Three Clear
- Property 1: North slope 85% cleared. Some residual grey streaking — full clearance expected by month 9
- Property 2: Fully clear. Shingles show original colour across all slopes
- Property 3: Fully clear. Minor preventative treatment may extend to 4-year cycle given south orientation
- Zero tenant complaints received in 6-month period. Gutter maintenance eliminated for review period
Clean
24 Months Post-Treatment
Portfolio Clean
- All three properties: zero active moss. Stage 1 spore activity on Property 1 north slope only
- Landlord insurance renewal: all three properties passed exterior condition review
- Rental market: clean roofs cited in two tenant lease renewals as positive property attribute
- Property manager has booked preventative retreatment for Properties 1 and 2 at 30-month mark
Architectural asphalt shingle — premium 50-year, installed 2015
Multi-building strata — varying orientations, mature fir canopy
Outcome Summary
- Roof Life Extended
- 10+ years across portfolio
- Replacement Cost Avoided
- $112,000
- Treatment Cost
- $2,200
- ROI
- 4,991%
- Warranty Status
- Active. Insurance deficiency notice withdrawn. 3-year maintenance contract established.
Initial Condition at Inspection
Stage 2–3 colonisation across 4-unit strata complex. Strata council received insurance underwriter notice flagging biological growth as maintenance deficiency. Gloeocapsa magma streaking across 3 of 4 buildings. Moss at ridge lines on all north-facing slopes. Strata had received quote of $112,000 for full replacement of all four roofs.
Cowichan Valley — cedar shake strata complex with water view
Property photograph — Vancouver Island.
Treatment Protocol
Strata portfolio protocol: sequential treatment across all four units over two days. Building 1 and 3 (heavier colonisation): standard 3% concentration, 30-minute dwell. Buildings 2 and 4 (lighter colonisation): preventative 1.5% concentration, 25-minute dwell. Common area gutters cleared pre- and post-treatment.
Documented Timeline
Pre / Day 0
Treatment Day
Four Buildings, Two Days
- Building 1: Stage 3 — full streaking, active moss ridge to eave on north slope
- Building 2: Stage 2 — light streaking, early moss at ridge only
- Building 3: Stage 2–3 — 60% streaking coverage, moss 1–2 cm at ridges
- Building 4: Stage 1–2 — minimal visible growth, preventative treatment warranted
- Insurance notice brought to site. Photographic documentation completed for underwriter response
Clearing
6 Months Post-Treatment
Strata Complex Clearing
- Buildings 1 and 3: 75% cleared. Heavy streaking transitioning from black to grey-brown
- Buildings 2 and 4: Fully clear. Preventative treatment achieved rapid surface clearance
- No active moss growth across any of the four buildings
- Strata submitted treatment documentation to insurance underwriter — deficiency notice withdrawn
- Property management company: zero maintenance complaints from 4-unit complex in review period
Clean
18 Months Post-Treatment
Full Portfolio Clean
- All four buildings: zero active biological growth
- Gloeocapsa streaking fully cleared on Buildings 1 and 3. Buildings 2 and 4 unchanged (already clear)
- Insurance renewal: all four buildings passed exterior condition assessment
- Strata council voted to establish 3-year scheduled maintenance contract
- Architectural shingle warranty re-confirmed active — no material damage documented
Documentation Method
Reference images shown are representative of property types and biological growth stages described — not the actual properties. Each case is recorded by the original treatment technician using a standard inspection form. Observations are made on-site, not remotely. Moisture meter readings, granule pull tests, and visual inspection notes are recorded at each visit.
Moss Stage Reference
Stage references (Stage 1–4) correspond to the colonisation model described in our Roof Biology section. Stage 1 = spore arrival. Stage 4 = structural damage underway.
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Contact Information
Phone
(250) 889-8490Service Area
Greater Victoria, BC
Sidney, Saanich, Langford
and surrounding areas
Business Hours
Monday - Friday: 8:00 AM - 6:00 PM
Saturday: 9:00 AM - 4:00 PM
Sunday: Closed