ROOF SUITABILITY · CEBU
Metal, concrete deck and tile roofs can all take solar, facing almost any direction at Cebu’s latitude. What decides it is space, shade, the strength of the roof and how many years it has left. Check yours in two minutes, then we confirm it on site.
Probably, if it has open space, little shade, a sound frame and years of life left. Plan on about 6.2 m² of open roof per kWp: a ₱10,000 monthly VECO bill (₱14.89/kWh, Sep 2026) suggests about 7 panels, roughly 27 m² of open roof on a simple roof (small or cut-up faces need more once a 1 m edge is kept clear). Direction matters little at Cebu’s latitude: east and west faces give only about 2–4% less a year than the best angle, a gentle north slope about 7% less.
The usual deal-breakers are heavy shade, a roof due for replacement, light materials, and missing permission from the owner or association. Each needs solving before solar makes sense.
01 · SPACE
Panels need open, unshaded roof with a clear margin at the edges. Here is the arithmetic our calculator uses, and where it falls short.
One of our 620 W N-type TOPCon panels measures 2.382 × 1.134 m, about 2.70 m². Not every square metre of roof can take one. Good practice keeps panels about 1 m back from eaves, ridges and gable edges, where wind uplift is strongest, unless the engineer’s calculation allows otherwise. Panels also work around vents, water tanks and shade.
For a roof you draw or type in, our calculator allows for all that by treating 70% of it as usable (where Google’s Solar API has your roof, it uses Google’s sunny-area estimate instead). That gives a planning figure of about 6.2 m² of open roof per kWp (4.4 m² of panel). On large, simple roofs it holds up well.
On a single face of a typical house, the clear edge takes a bigger share. The plan shows a 12 × 7 m face (84 m²) that fits 16 panels, fewer than the ratio suggests. That is why every quote follows a drawn layout from the site assessment, not a rule of thumb.
2.70 m²per 620 W panel2.382 × 1.134 m
≈6.2 m²of roof per kWpat 70% usable
1 mclear edgegood practice; estimate
12 m along the ridge × 7 m down the slope, with 1 m kept clear at every edge (hatched).
Illustration, not a design. A plain 12 × 7 m face with a 1 m clear edge holds 16 panels laid landscape. The 70% rule of thumb would suggest 21, which is why the drawn layout, not a ratio, sets the final count.
| Monthly bill | Panels | Panel area | Roof to plan for | Average output |
|---|---|---|---|---|
| ₱4,000≈ 269 kWh | 4*2.48 kWp | 11 m² | ≈ 15 m² | ≈ 280kWh/month |
| ₱7,000≈ 470 kWh | 53.10 kWp | 14 m² | ≈ 19 m² | ≈ 350kWh/month |
| ₱10,000≈ 672 kWh | 74.34 kWp | 19 m² | ≈ 27 m² | ≈ 490kWh/month |
| ₱15,000≈ 1007 kWh | 116.82 kWp | 30 m² | ≈ 42 m² | ≈ 770kWh/month |
| ₱20,000≈ 1343 kWh | 148.68 kWp | 38 m² | ≈ 54 m² | ≈ 980kWh/month |
Estimates from our calculator’s solar-only sizing at VECO’s Sep 2026 rate of ₱14.89/kWh, with roof area at the 70% allowance; not a design. The solar-only option aims to cover about 70% of your yearly use. Output uses our cautious 1,350 kWh per kWp a year and varies by month. *4 panels is our smallest system. Prices for each size are in our solar installation cost guide and our solar packages.
Know your bill? The calculator sizes the system, checks it against your roof (draw it on the map or type its area) and shows an itemised price in about 30 seconds.
Estimate my system size and price02 · YOUR ROOF
Eight questions. Each answer gets a traffic light with a plain reason, and the report adds up what your roof could hold and what to have ready for the visit.
Roof assessment checklist
8 questions · about 2 minutes · no sign-upWe’ve filled in an example so you can see how it works: a sound metal roof facing east, about 50 m², near the sea. Change any answer to make it yours.
Example7 good · 1 check · 0 issue · 12 panels
See reportBEFORE THE VISIT
Example roof: 7 good, 1 to check on site, 0 likely issues. About 12 panels.
Estimates for planning, not a survey. Space uses our calculator’s 70% usable-roof allowance and 2.70 m² per 620 W panel. Output uses our cautious 1,350 kWh per kWp a year, reduced by the PVGIS loss for your roof direction. Photos can be shared when we call: this page doesn’t upload them.
03 · ROOF TYPE
The roof material decides the mounting, the leak protection and what we look at most closely on site.
GI, long-span, rib-type
Brackets bolt through the sheet into the purlins or rafters, with a sealing washer at every screw, and carry the rails. Never into the sheet alone.
Flat RC slab, roof deck
Panels sit on low frames tilted about 5–15°, mechanically anchored into the slab rather than held down by weight or glue, with the anchors designed for the load. Every anchor passes through the waterproofing, so each one is sealed.
Clay or concrete tile
Hooks fix to the rafters or battens under the tiles and come out between them, so the hook, not the tile, carries the load. Some tiles are notched or swapped for spares. Hook type and spacing follow the mounting maker’s manual.
Cross-sections are illustrations, not to scale. The exact brackets, hooks and anchors are specified in your proposal.
| Metal sheet | Concrete deck | Tile | Light materials | |
|---|---|---|---|---|
| How panels are fixed | Brackets through the sheet into purlins or rafters | Low frames anchored into the slab | Hooks to rafters or battens, between tiles | Not possible as built |
| Leak protection | Sealing washer at every screw | Each anchor sealed over the waterproofing | Tiles refitted over the hooks | — |
| What we look at hardest | Purlins, spacing, rust, sheet fastening | Slab condition, waterproofing, drains | Rafters, battens, brittle tiles | A new roof design |
| Usual verdict | Usually straightforward | Usually straightforward | Possible, with care | Rebuild the roof first |
Metal sheet
Usually straightforwardConcrete deck
Usually straightforwardTile
Possible, with careLight materials
Rebuild the roof firstNot sure what’s under your roofing? That’s what the site assessment is for: we look at the frame, the fixings and the condition before anything is priced.
Request my solar roof assessment04 · DIRECTION AND TILT
Cebu City sits at about 10.3° N, close enough to the equator that the sun passes high overhead all year. Direction changes yearly output by a few per cent, not by half.
Difference from the best angle, all ten runs
kWh per kWp per year. PVGIS 5.3, PVGIS-ERA5 2005–2023, 14% system loss, Cebu City. Our calculator starts from a more cautious 1,350.
A south face at about 13° gives the most in PVGIS, 1,418 kWh per kWp a year. Flat panels lose only about 1%.
East faces lose about 2%, west faces 4%. Morning and afternoon faces both work well. A gable roof facing east and west can carry panels on both sides.
About 2% less at 5°, 7% at 15° and 14% at 25°. From about mid-April to late August the midday sun is slightly north of overhead in Cebu, part of why north faces lose so little.
No tall frames needed: a low tilt does almost as well as the best angle and catches less wind. Many installers avoid perfectly flat panels so rain can rinse them, a matter of practice rather than a rule.
05 · SHADE
A gentle north slope loses a few per cent a year. A shaded panel loses most of its output for as long as the shade lasts.
Panels are wired in strings, so one shaded panel can hold back others on the same string. That is why panel makers advise against permanent shade (Jinko’s installation manual, for example, says it is “not recommended”).
When the shade falls matters as much as how long it lasts. On an idealised clear day, two hours of shade from 6 a.m. costs a shaded panel about 7% of the day’s energy; the same two hours around noon cost about 26%. Try your own shade window below.
13% of a clear day’s energy
Shade from 7 a.m. to 9 a.m. costs the shaded panels about 13% of a sunny day’s output. The same 2 hours centred on noon would cost about 26%.
Mango, acacia and coconut trees keep growing. One that clears the roof today may not in five years, so ask whether it can be trimmed.
In close subdivisions, a two- or three-storey house next door can shade a bungalow roof for part of the day.
Elevated tanks on a roof deck cast long shadows in the morning and late afternoon.
On concrete decks, parapets shade the first row when the sun is low, so frames are set back from them.
Small but sharp shadows sweep across panels during the day. Moving a dish is often easy.
06 · STRUCTURE AND AGE
Panels add wind uplift to the roof, and they stay up for decades. Both are reasons to look at the frame and the roof’s remaining life before anything else.
Every bracket passes its load into the frame under the roofing, so that is where we look: the size and spacing of the purlins or rafters, how they connect to the trusses, rust on steel, termite damage in timber, and whether the roof sheets themselves are well fastened.
Panels are expected to stay up for 25 years or more, so the roof under them should have at least that much life left. FEMA’s guidance, citing the US National Roofing Contractors Association, puts it plainly: the roof’s remaining service life should be at least the life of the solar system. If yours is due for replacement in the next few years, do it first. Otherwise you pay to remove and refit the panels later.
The electrical plans for your permit must be signed and sealed by a Professional Electrical Engineer (RA 7920). Whether your city or municipality also wants a building permit or a structural sign-off for rooftop solar varies, and we confirm it for your address.
In FEMA’s study after the 2017 hurricanes in the US Virgin Islands, whole rows of panels were lost when clamps and their bolts let go, while the mounts themselves held. So the fixing method, the clamp hardware and the wind design for your site matter more than the panel’s datasheet. Our typhoon-ready installation guide covers wind design, coastal corrosion and what to do before and after a storm.
During the site assessment, before any final price.
07 · ACCESS AND UPKEEP
A roof that’s hard to reach is hard to install on and hard to look after. These are the practical checks people forget.
Installers need stairs to the deck or a safe ladder spot. Three-storey homes and steep roofs may need scaffolding or anchor points; we tell you during the assessment if they’re needed.
Gaps between rows leave room to reach every clamp for yearly checks without stepping on panels.
Rain rinses panels for much of the year. In dry spells, dust and bird droppings build up; a rinse with water from a safe position is usually enough. Never walk on panels.
Panels should never cover roof drains or gutters, so water still gets away in a downpour and you can still clear them.
Deye’s SG05LP1 datasheet lists IP65 and output derating above 45 °C, so the inverter goes on a shaded, ventilated wall, with the battery, above any flood level.
08 · PERMISSION
The roof has to be yours to change, or someone has to agree in writing. Sort this out before the site visit.
You usually own your roof, but your homeowners’ association may have rules on roof works, appearance or contractors’ working hours. Check them early.
In most buildings the roof is common property, so you need written approval from the building owner or condominium corporation, a roof area assigned to you and a safe cable route to your own meter.
Solar is fixed to the building, so the owner must agree in writing. Net-metering applications can also ask for proof of ownership: Visayan Electric lists it among its application documents.
09 · YOUR UTILITY
Every home connects to a neighbourhood transformer, and utilities cap how much solar each one can host. VECO and MECO publish guide tables at about 30% of a transformer’s rating, so a 25 kVA transformer hosts about 7.5–8 kW of solar. CEBECO I uses 40%.
VECO now also publishes capacity by substation and feeder. Its table dated 15 October 2026 shows 11 of its 65 listed feeders with no remaining capacity. So the utility’s impact study, free to the customer, decides what can be connected and exported at your address. Our net-metering guide explains the application, and the utility guides cover each area.
≈30%VECO and MECOof a transformer’s kVA, guide tables
40%CEBECO Iof a transformer’s kVA
11 of 65VECO feeders at 0 MWtable dated 15 Oct 2026
₱0impact study feeERC net-metering rules, 2025
10 · THE SITE ASSESSMENT
From your desk to a final design, in four steps. Nothing is priced as final until the roof and wiring have been seen.
Your roof assessment, step by step
01 / 04Chapter 01
Step 1 · From your desk
Start with this checklist and our calculator. Where Google has data for your address, the calculator reads Google’s Solar API estimate of your sunny roof area; elsewhere you can draw your roof on the map or type in its size. Your bill sizes the system before anyone climbs a ladder.
A first design and price range before the visit.
Chapter 02
Step 2 · Site assessment
Each roof face is measured and its direction and slope noted. We map shade from trees, tanks and neighbouring floors, check the frame under the roofing and the condition of the sheets or tiles, and plan where rails, walkways and cable entries go.
A drawn panel layout instead of a rule of thumb.
Chapter 03
Step 3 · Electrical check
We check your service entrance, main breaker panel, earthing and space for new breakers, and confirm your supply is single-phase, which our Deye hybrid inverters need. The inverter and any battery go on a shaded, ventilated wall above flood level. If you want brownout backup, we agree which circuits stay on.
A wiring plan that fits your house.
Chapter 04
Step 4 · Design and quote
You receive the layout, the equipment list and an itemised price that includes permits and net-metering paperwork. Warranty terms are confirmed in your proposal. Compare it line by line with any other offer using our guide to comparing solar quotes.
A quote based on your actual roof.
At your pace. Select any chapter.
Ready for step 2? We’ll call to arrange the visit, and you can share roof photos then.
Request my solar roof assessmentScenes are illustrations, not photos of an installation. See the whole journey on how solar works, or browse all our solar guides.
STRAIGHT ANSWERS
Common questions about roofs, with the numbers behind the answers.
Yes. Metal sheet roofs are among the simplest to mount on. Brackets fix through the sheet into the purlins or rafters with a sealing washer at each screw, never to the sheet alone, and the rails and panels sit on those brackets. During the site assessment we check purlin size, spacing and rust, and how the sheets themselves are fastened.
On standing-seam roofs, clamps can grip the seams instead, so nothing pierces the sheet.
They shouldn’t, as long as every fixing is sealed. On metal roofs each screw gets a sealing washer; on concrete decks each anchor is sealed over the waterproofing; on tile roofs the hooks pass between tiles that are put back over them. Leaks usually come from fixings that miss the purlin, unsealed penetrations or panels laid over drains.
If your roof already leaks, fix it before installation. Repairs under an array mean taking panels off.
Usually, yes. In PVGIS data for Cebu City, a north face tilted 15° gives about 7% less a year than the best angle, and at 5° only about 2% less. Steep north faces lose more: about 14% at 25°. If you have a free east, west or south face we’d use that first, but a north face is often still worth it.
At Cebu’s latitude a south-facing tilt of about 13° gives the most energy in PVGIS (1,418 kWh per kWp a year), but anything from flat to about 20° is within about 1% of it. On sloped roofs panels simply follow the roof. On flat concrete decks we use low frames of about 5–15°: tall frames gain almost nothing here and catch more wind.
Check how much life it has left first. Panels stay up for 25 years or more, and the roof under them should last at least as long. If the roof leaks, sags, is badly rusted or is due for replacement in the next few years, replace it before installing; otherwise you pay to remove and refit the panels later.
Our site assessment checks the roof’s condition before any price is final.
Roofs in shade for most of the day, roofs built from light materials such as nipa or thin board, roofs near the end of their life, and very small roofs with room for fewer than 4 panels once the edges are kept clear. Within about 50 m of the shore the design changes: some panel makers (Jinko, for example) set 50 m as their minimum distance and recommend marine-rated modules closer in. A shared or rented roof works only with the owner’s written permission.
On a townhouse you usually own your roof, but check your homeowners’ association rules first. In most apartment buildings and condominiums the roof is common property, so you need written approval from the building owner or condominium corporation, a roof area assigned to you, and a cable route to your own meter. If you rent, the owner must agree in writing, and net-metering applications can ask for proof of ownership.
As a planning figure, about 6.2 m² of open roof per kWp. A ₱10,000 monthly VECO bill (₱14.89/kWh, Sep 2026) suggests about 7 panels, or roughly 27 m² of roof. Small, hipped or cut-up roofs fit fewer panels once a clear edge of about a metre is kept, so we confirm the count with a drawn layout during the site assessment.
THREE WAYS TO MOVE FORWARD
Request a site assessment, run your own numbers first, or ask a question. Answers you gave in the checklist travel with your request.
Share a few details and we’ll prepare a proposal after a site assessment.
Request my quoteRoute AYour system, installed price and savings in about 30 seconds. No contact details needed.
Start the calculatorRoute CHave a question first? Ask it here and get a straight answer.
Ask a questionROUTES B & C · TALK TO US
Every quotation follows a site assessment of your roof, wiring and priorities, so the price you approve is the price of the system you get.
Tell us where the house is and what the roof is like. We’ll call to arrange a visit, and you can share roof photos then.
Not ready for a quote? Ask about whether your roof suits solar and we’ll reply by phone or email.
ROUTE A · INSTANT ESTIMATE
The same calculator and prices as the rest of the site. Your estimate stays on your screen unless you ask us to contact you.
Your promo code takes 10% off your system estimate, up to ₱50,000.
Choose your usual monthly bill. An estimate is all you need.
Using VECO at ₱14.89/kWh · Sep 2026. You can change your provider later.
About 30 seconds · No obligation
Reviewed 16 October 2026 · Panel counts and output recalculated from our calculator’s maths; VECO rate ₱14.89/kWh (Sep 2026)
Grid-connected PV run for 10.3157° N, 123.8854° E, PVGIS-ERA5 2005–2023, 1 kWp, 14% system loss. Optimum 1,418 kWh/kWp at 13° south; ten orientations compared.
Clamp failures, through-fixing to the structure, no ballast-only systems in hurricane regions, roof service life, walkways, drains and yearly clamp checks.
One major manufacturer’s manual, cited as an example of coastal and shading rules: permanent shading not recommended; 50 m minimum from the seashore and connector protection from 50 to 500 m. Your proposal names the actual module and its manual.
IP65; output derates above 45 °C.
NSCP 2015 wind provisions are based on ASCE 7-10. The ~1 m clear edge is our estimate from ASCE 7-10 edge-zone widths for a typical house; the engineer’s calculation decides.
About 30% of transformer kVA, e.g. 25 kVA → 7.5 kW. For initial guidance only.
11 of the 65 listed 23 kV feeders at 0.00 MW.
About 30% of transformer kVA for single-phase transformers without PV.
Hosting table at 40% of transformer kVA.
Distribution impact study at no cost to the customer.
Documents listed include IDs and proof of ownership.
RE facilities built without a building permit must secure one first (§5.1, §6). Cebu LGU practice for rooftop PV not yet confirmed.
Electrical plans must be signed and sealed by a Professional Electrical Engineer (Sec. 31, 34).
YOUR ROOF, CHECKED
A site assessment measures every face, maps the shade and checks the structure and wiring, so the quote you approve fits your actual roof. No obligation.
YOUR NEXT QUESTION
Each guide answers one question properly, with the numbers and sources behind it.