Mr Quyen - Santiago. Posted 03/11/2026
On the Kenyan coast an ASA/PVC tile sheet has no metal in it, so salt air in Mombasa, Diani, Malindi or Lamu has nothing in the sheet to rust. The metal left on the roof is the screws: ask your installer for stainless or coated 70 mm screws under the ASA caps. A small beach hotel with 8 cottages and a restaurant (about 658 m² of roof) needs about 3,290 screw sets at 5 per m².
Dark grey tile-sheet roof above a bay, Ba Ria – Vung Tau, Vietnam
Why do metal roofs age early on the Kenyan coast?
Along the coast from Lamu down to Diani, the wind off the Indian Ocean carries salt, and the air stays humid most of the year. Salt settles on a roof, the humidity keeps it damp, and on a steel sheet rust begins where the coating is broken: at screw holes, at the laps and along cut edges. Hotel and beach-house owners know the result. The roof needs paint or replacement long before the building around it is old.
A Santiago ASA/PVC tile sheet has no metal in it. It is 2.5 or 3.0 mm thick, made of four co-extruded layers with no glue: an ASA top layer, virgin PVC, a PVC core and a milky-white PVC base. Salt can sit on it and the sheet does not corrode. The ASA top layer also deals with the coastal sun: no colour change after 2,000 hours of artificial UV in testing, and a colour rating of 30 years.
What on a coastal roof can still rust?
A roof is more than its sheets. Before you build at the coast, go through every part and decide what it is made of:
| Part of the roof | Material | What to do at the coast |
|---|---|---|
| Tile sheets and ridge pieces | ASA/PVC (Santiago) | No metal, no rust |
| Screw caps | ASA (Santiago) | One over every screw head; they cover the head from salt and rain |
| Screws, 70 mm | Metal | Ask your installer for stainless steel or coated screws, and confirm in writing who supplies them |
| Purlins and roof frame | Timber or steel, from your builder | The sheet keeps rain off, but salt air reaches the underside; protect the frame as your engineer specifies |
| Gutters and downpipes | From your builder | Choose a material that suits salt air |
Settle the screw material, and who supplies the screws, with your installer at the quotation stage, not on the day the roof goes on. The ASA cap goes over every screw head whatever the screw is made of.
Which coastal buildings suit a tile-sheet roof?
- Beach houses and holiday cottages in Diani, Watamu or Malindi, where a tile look suits the setting
- Small hotels and guesthouses: guest rooms stay about 6 – 8 °C cooler than under bare metal sheet and rain is about 80% quieter (Santiago tests)
- Restaurants and open bandas or pavilions facing the sea
- Staff housing, kitchens and stores, in 5-wave or 6-wave corrugated sheet
- In Lamu, check with the county before changing any roof in an old-town area
Yellow two-storey building with a dark grey tile-sheet roof, Ba Ria – Vung Tau, Vietnam
Worked example: fixings for a beach hotel with 8 cottages and a restaurant
Sea wind is the reason to build to the tighter end of Santiago's figures at the coast: purlins at 440 mm and 5 screw sets per m². This example counts the sheets and the fixings for a small hotel. Each cottage has a gable roof 7.68 m long (8 sheets per face) with 3,504 mm faces (16 tile steps). The restaurant has a gable roof 19.2 m long (20 sheets per face) with 5,913 mm faces (27 steps).
| Item | 8 cottages | Restaurant | Total |
|---|---|---|---|
| Sheets | 8 × 16 = 128 of 3,504 mm | 40 of 5,913 mm | 168 sheets, about 685 running metres |
| Roof area | 8 × 53.8 m² = 430.6 m² | 227.1 m² | about 658 m² |
| Screw sets at 5 per m² | about 2,150 | about 1,140 | about 3,290 screws and 3,290 ASA caps |
| Ridge cap | 8 × 7.68 m = 61.4 m | 19.2 m | about 80.6 m |
| Ridge terminals | 16 | 2 | 18 |
| Eave sealing tile | 8 × 15.36 m = 122.9 m | 38.4 m | about 161.3 m |
| Sheet weight at 5.4 kg per m² | about 2,325 kg | about 1,226 kg | about 3,550 kg |
The screw count is the line to give your installer first. About 3,290 stainless or coated 70 mm screws is a real purchase, and it should be priced into the job from the start. The whole hotel uses about 685 m of sheet, far below the 5,000 m minimum order, so a coastal dealer or developer usually combines it with other projects or yard stock in one container.
How do you import tile sheets through Mombasa port?
Santiago ships by the 40 ft container, about 5,000 m of sheet, with colours, profiles and accessories mixed. Production takes about 5 days and the goods ship under HS code 3925.90.00. Kenya has no trade-agreement preference with Vietnam for this product, so check the duty rate with your clearing agent in Mombasa, and ask which inspection or conformity papers are needed for roofing sheet before you place the order.
Each shipment comes with a commercial invoice, packing list, bill of lading, a certificate of origin issued in Vietnam if your agent needs one, and a quality certificate (CQ) for every lot. Santiago's quality system holds ISO 9001:2015 certificate ICI-23087.D, and the sheet has Quatest test results. Prices are quoted per order in writing. Samples are free; the buyer pays the courier.
Coastal installation checklist
- Slope between 20% and 45%.
- Purlins at 440 mm, one under the foot of each tile step; top purlin 15 – 18 cm below the ridge.
- Stainless steel or coated 70 mm screws, agreed in writing.
- Pre-drill 6 mm holes through the top of the wave, directly over a purlin; never screw in the valley.
- 5 screw sets per m², an ASA cap on every screw.
- Lap each sheet over the next by one wave.
- Fit ridge cap, ridge terminals and eave sealing tiles in the same colour.
Santiago supplies sheets and accessories and sends installation videos; it does not install. The warranty is 10 years for 2.5 mm and thicker when the roof is installed as Santiago recommends. For the inland comparison with mabati and a bungalow example, see best roofing sheets in Kenya.
How do PVC roofing tiles cope with sun, rain and wind?
The short opens with red ASA/PVC tile sheets being carried up to a house, then a flame is put to a stack of tile sheets made from virgin PVC with an ASA top layer. It ends on a blue warehouse roof under installation and grey tile sheets on a roller line at the factory, with the WhatsApp number +84 935 391 495 on screen.
Santiago PVC roofing tiles in real conditions (Santiago video on YouTube).
More shorts for the Kenyan coast
The clips below come from Santiago's own YouTube channel and were filmed at the factory in Vietnam or on Santiago roofs.
What do the top and underside of the sheet look like?
A short factory clip: a white tile sheet takes a worker's weight on the floor, a torch is aimed at red and blue sheets, and the Santiago team lines up in front of a container.
Santiago tile sheets at the factory (Santiago video on YouTube).
What does a grey tile roof look like next to the gutter?
In under a minute the short goes from the Santiago factory floor to a grey tile-profile roof on site: some sheets already fixed, installers screwing down the rest, and a finished run next to the gutter.
Santiago uPVC tile roofs on site (Santiago video on YouTube).
What do the yard tests on blue and red sheets show?
Three quick scenes from Santiago: a ridge piece under a truck wheel, a torch held to blue and red tile sheets in the yard, and strapped bundles of sheets waiting for loading.
Truck, flame and packing: Santiago ASA/PVC sheets at the factory (Santiago video on YouTube).
Santiago – a leading exporter of ASA/PVC roofing from Vietnam
Santiago roofing is produced and loaded into containers at our factory in Vietnam. It has been exported to India since 2023, Thailand since 2024 and the USA since 2025. Every export shipment comes with a commercial invoice, packing list, bill of lading and a certificate of origin (C/O) issued by Vietnam's Ministry of Industry and Trade, which importers use to claim the duty preference of their trade agreement.
| Item | Details |
|---|---|
| HS code | 3925.90.00 (ASA/PVC roofing sheets) |
| Certificate of origin | Form D (ASEAN), Form AI (India), Form AK / VK (Korea), Form AJ / VJ (Japan), Form VC (Chile), CPTPP proof of origin |
| Shipped from | Vietnam, by container |
Certificate of origin Form AI (ASEAN–India) for Santiago ASA/PVC roofing sheets, HS 39259000, certified on 24 September 2026. Buyer details are hidden.
The Santiago team beside a loaded export container at the factory, November 2024
Loading Santiago roof tiles into an export container
Frequently asked questions
Does an ASA/PVC roof rust at the coast?
The sheet has no metal, so it does not rust. The screws are metal: ask your installer for stainless steel or coated 70 mm screws and cover each head with an ASA cap.
Who supplies the screws for a coastal roof?
Agree the screw material and the supplier with your installer and in the quotation. Santiago supplies the sheets, ridge pieces and ASA screw caps.
How many screws does a 658 m² coastal hotel roof need?
About 3,290 screw sets at 5 per m², the figure Santiago suggests for windy sites, with an ASA cap on each.
Can I import tile sheets through Mombasa?
Yes, by the 40 ft container, about 5,000 m of sheet. Your clearing agent confirms the duty rate and the papers needed.
Read more
- A rust-free roof: ASA/PVC sheets and FRP purlins
- Screws and ASA caps: fixing through the top of the wave
- Coastal home roofing and salt air
- Best roofing sheets in Kenya: mabati or PVC tile sheet
- ASA/PVC roof tile sheet
Toleo la Kiswahili
Pwani ya Kenya, bati la vigae la ASA/PVC halina chuma, kwa hiyo hewa ya chumvi ya Mombasa, Diani, Malindi au Lamu haina cha kushika kutu kwenye bati. Chuma kinachobaki paani ni skrubu: mwombe fundi wako skrubu za mm 70 za chuma cha pua (stainless) au zilizopakwa kinga, chini ya vifuniko vya ASA. Hoteli ndogo yenye nyumba 8 na mgahawa (takriban m² 658 za paa) inahitaji takriban seti 3,290 za skrubu.
Kwa nini mabati hushika kutu haraka pwani?
Upepo wa Bahari ya Hindi huleta chumvi, na unyevu wa pwani huifanya ibaki juu ya paa. Kwenye bati la chuma, kutu huanzia pale kinga imeharibika: kwenye matundu ya skrubu, maungio na kingo zilizokatwa. Bati la vigae la Santiago lina tabaka nne bila gundi, na tabaka la juu la ASA. Halina chuma, kwa hiyo chumvi haiwezi kulifanya lishike kutu. Rangi haikubadilika baada ya saa 2,000 za mwanga wa UV kwenye majaribio, na rangi imekadiriwa kudumu miaka 30.
Ni nini bado kinaweza kushika kutu?
| Sehemu ya paa | Ushauri kwa pwani |
|---|---|
| Mabati ya vigae na vipande vya kilele | ASA/PVC, hayashiki kutu |
| Vifuniko vya skrubu | ASA, kimoja juu ya kila skrubu |
| Skrubu za mm 70 | Za chuma cha pua au zilizopakwa kinga; kubalianeni kwa maandishi nani atazileta |
| Purlin na kenchi | Zilindwe kama mhandisi wako anavyoelekeza |
| Mifereji ya maji | Chagua kitu kisichoshika kutu kwa urahisi |
Kubalianeni na fundi wako aina ya skrubu na nani atazileta wakati wa kupokea bei, si siku ya kuezeka.
Nyumba ya bluu yenye paa la vigae vya kijivu kilichokolea kando ya bahari, Ba Ria – Vung Tau, Vietnam
Ni majengo gani ya pwani yanafaa paa la vigae?
Nyumba za ufukweni na nyumba za likizo huko Diani, Watamu na Malindi hupata mwonekano wa vigae bila uzito wa vigae vya udongo. Kwenye hoteli ndogo na nyumba za wageni, vyumba hubaki baridi zaidi kwa takriban 6 – 8 °C kuliko chini ya mabati yasiyo na kinga, na kelele ya mvua hupungua kwa takriban 80% (majaribio ya Santiago). Migahawa na mabanda yanayoelekea bahari pia yanafaa. Stoo, jikoni na nyumba za wafanyakazi zinaweza kutumia bati la mawimbi 5 au 6. Huko Lamu, wasiliana na kaunti kabla ya kubadilisha paa lolote katika eneo la mji wa kale.
Mfano: hoteli ndogo ya ufukweni
Hoteli ina nyumba ndogo 8, kila moja na paa la m 7.68 lenye pande za mm 3,504, na mgahawa wenye paa la m 19.2 lenye pande za mm 5,913. Jumla ni mabati 168 (takriban m 685) na takriban m² 658 za paa. Kwa sababu ya upepo wa bahari, tumia purlin kila mm 440 na seti 5 za skrubu kwa kila m²: takriban skrubu 3,290 na vifuniko 3,290 vya ASA. Kofia ya kilele ni takriban m 80.6, na vifuniko vya mwisho wa kilele ni 18.
Kuagiza kupitia bandari ya Mombasa
Santiago husafirisha kwa kontena la futi 40, takriban m 5,000 za mabati, na rangi na vifaa vinaweza kuchanganywa. Uzalishaji huchukua takriban siku 5. Kenya haina makubaliano ya biashara yanayopunguza ushuru wa bidhaa hii kutoka Vietnam, kwa hiyo uliza kiwango cha ushuru na nyaraka zinazohitajika kwa wakala wako wa forodha (HS code 3925.90.00). Bei hutolewa kwa maandishi kwa kila oda, na sampuli ni bure; mnunuzi analipia usafiri wa kifurushi. Santiago haifanyi ufungaji, lakini hutuma video za ufungaji.
Banda wazi lenye paa la vigae vya kijivu kilichokolea karibu na pwani, Ba Ria – Vung Tau, Vietnam
Maswali yanayoulizwa mara kwa mara
Je, paa la ASA/PVC hushika kutu pwani?
Hapana, bati halina chuma. Skrubu ndizo za chuma, kwa hiyo tumia za chuma cha pua au zilizopakwa kinga, na kifuniko cha ASA juu ya kila moja.
Hoteli ya m² 658 inahitaji skrubu ngapi?
Takriban seti 3,290, kwa kiwango cha seti 5 kwa kila m² kwenye maeneo yenye upepo.
Naweza kuagiza mabati ya vigae kupitia Mombasa?
Ndiyo, kwa kontena la futi 40, takriban m 5,000 za mabati. Wakala wa forodha atathibitisha ushuru na nyaraka.
Sources for the figures in this article
- Profiles, 2.5–3.0 mm thickness and 10-year warranty: Santiago ASA/PVC product specification.
- About 6–8 °C cooler than bare metal sheet and about 80% less rain noise: Santiago's own comparisons on finished roofs in Vietnam.
- HS code 3925.90.00: Harmonized System Chapter 39 (builders' ware of plastics), as applied in Vietnam's export tariff.
- Certificates of origin (Form D, AI, AK/VK, AJ/VJ, VC, CPTPP): issued by Vietnam's Ministry of Industry and Trade under the country's free trade agreements.
- Minimum order of one 40 ft container (about 5,000 m) and about 5 days for production and loading: Santiago export desk, October 2026.
Updated 03/11/2026. Santiago Import Export Co., Ltd, Vietnam. WhatsApp +84 935 391 495 (Mr. Quyen), hotline +84 965 437 316 (Mrs. Ly), email salessantiagoroofing@gmail.com.
