Cooling Lot 922

West-sun heat plan for a shingle-roof concrete house: shade first, attic fix second, trees for the long term — sourced in Barbados

13 stores + 5 nurseries checked · 15 Aug 2026 · rev 3 (draggable AC markers)

4 levers2 planting routes2 stores phone-first
Contents

    Verdict

    The 4–5pm heat is the low western sun cooking the long concrete west wall, plus a shingle roof that collects heat all day. Trees will genuinely help, and the west side you can access is exactly the right side to plant — but since shingles can't be coated, the order is: shade the west windows now, cut the attic heat with a radiant barrier and turbine vents, and let the trees be the long-term layer.

    ~70%
    of tropical house heat gain comes through the roof [4]
    5–20°C
    cooler wall surface when shaded [3]
    10–20%
    cooling energy saved by west-side trees in hot climates [1]
    ~40%
    less attic heat flow with a radiant barrier under the shingles [11]
    Primary recommendation Do the four layers in this order: 1) exterior shade on the west windows now (PriceSmart Coolaroo roller shade, in stock), 2) radiant barrier + turbine vents in the roof void — the shingle-safe roof fix (turbines in stock at three stores, ~BBD $350), 3) sea grape + frangipani on the west/northwest arc this wet season, 4) only then decide on the AC upgrade, sized to the reduced load. Coating the roof is parked until you re-roof: shingle makers' own association says never coat shingles in place [10] — when the re-roof eventually happens, that's the moment for light "cool" shingles or white metal.

    Why it gets hot at 4–5pm

    Barbados sits at ~13°N. In summer the sun sets slightly north of due west (azimuth ~284–292°), and by 4–5pm it is low enough to hit vertical walls almost square-on — the worst geometry for a wall. Your drawings show the house's long axis runs roughly north–south, so the long west facade takes that hit. Concrete then re-radiates the absorbed heat indoors for 4–8 hours (thermal lag), which is why the evenings stay hot with the windows shut and the AC running: the heat is coming through the wall and roof, not past the curtains.

    lot boundary neighbour — tight gap, no access HOUSE long axis ≈ N–S deck (back, roller screens planned) LR BR GYM 4–5pm sun (W/WNW) trees 3–4.5 m off the west wall N W E
    Schematic from the Lot 922 deck plan set — not to scale.
    Drag the AC units where they really are The three orange boxes — LR (living room), BR (bedroom) and GYM — are draggable. Drag each one to its true position and the page remembers it on this device. Reset positions

    Their exact position does not change any of the four recommendations below. The condensers only carry one rule, and it travels with the unit wherever it sits: keep 60–90 cm clear on every side and open above, so nothing — planting, deck furniture, or a future roller screen — traps its hot exhaust [6]. Marking them is for planning around, not a reason to re-rank the plan.

    Good news: the side you can work on (west) is the side that matters. The tight eastern gap is fine to leave alone — morning sun is higher and milder, and nothing should be planted in a boundary gap that narrow anyway.

    The four levers, ranked

    1. Exterior shade on west windows & wall

    Works the day you install it, while everything else ramps up. Exterior beats interior blinds because it stops heat before the glass and concrete. Roller shades, shade sails, or a 70% shade cloth stood 10–15 cm off the hottest wall section (ventilated gap).
    ✓ do now

    2. Attic fix: radiant barrier + turbine vents

    The roof is ~70% of heat gain in tropical houses [4], but shingles must never be coated in place — the shingle manufacturers' association warns it curls shingles, traps moisture and voids warranties [10]. What does work under shingles: double-sided foil radiant barrier stapled under the rafters (~40% less attic heat flow, 5–10% off cooling costs [11]) plus turbine vents with open soffit intake to flush the hot attic air. When you eventually re-roof, choose light "cool" shingles or white metal.
    ✓ the shingle-safe roof fix

    3. Trees on the west/northwest arc

    West-side shade trees produce the largest cooling savings of any position — 10–20% of annual cooling energy in hot climates [1][2], with shaded walls 5–20°C cooler [3]. Needs 3–5 years to mature; plant this wet season.
    ✓ plant this season

    4. AC upgrade — last, not first

    Upgrading first fights the symptom at a higher power bill. Cut the load with 1–3, then size the replacement (ideally inverter) to the reduced load. Three condensers serve the living room, the bedroom and the gym: keep 60–90 cm clear around each and open above, wherever they sit — shading a condenser saves only 1–3% and blocked airflow makes it worse [6].
    ✗ don't start here

    Buy it in Barbados — checked 15 Aug 2026

    Attic-heat kit (works under shingles)

    StoreProductPrice BBDStatusLink
    KooymanMaster Flow rotary turbine ventilator, 14 in$348.13⚠ webshop closed — phone firstView
    H&B HardwareTurbine vent + base, galvanised, 12 in$354.99✓ listed in stockView
    Carter'sAluminium braced wind turbine attic vent, 14 in$356.75✓ listed in stockView
    Do it BestReflectix double-reflective insulation, 24 in × 50 ft$250.71⚠ special order — unreliableView
    Carter'sReflective foil tape (for barrier seams), 2 in × 30 ft$14.76✓ listed in stockView
    Radiant-barrier sourcing note Turbine vents are easy — three stores stock them around BBD $350, and a roofer fits one plus soffit intake in half a day. The foil itself is the gap: the only on-island listing found is a Do it Best special order, which in past experience doesn't reliably materialise. Phone Carter's / H&B / Kooyman for "double-sided foil insulation" first; if nobody stocks a roll, freight-forward one — a Reflectix roll is light and ships fine.
    Parked until you re-roof: white-coating prices found on-island

    Shingle roofs must not be coated in place [10] — this table is saved for the future re-roof decision only (or for any flat concrete section). Prices checked 15 Aug 2026.

    StoreProductPrice BBDStatusLink
    KooymanHarris Ulttima Roof Coating White, 1 gal$109.99webshop closed — phoneView
    H&B HardwareAPOC Elastomeric Kool 700, 1 gal$114.50confirmed in stockView
    H&B HardwareAPOC #243 Elastomeric Coating White, 1 gal$162.04confirmed in stockView
    H&B HardwareRoof Elastomeric Coating White, 5 gal$491.98confirmed in stockView
    KooymanHenry Elastomeric Roof Coating White, 5 gal$339.89webshop closed — phoneView
    Do it BestKool Seal White Acrylic Elastomeric, 4.75 gal$428.35phone to confirmView
    Kooyman caveat kooymanbv.com showed a site-wide "Temporary Closure" notice on 15 Aug 2026 — Kooyman prices here are directory-cached, not live. Call or visit before making the trip. Do it Best special-order items are flagged deliberately; their special orders are unreliable.

    Exterior shade for the west windows

    StoreProductPrice BBDStatusLink
    PriceSmart (St. Michael)Coolaroo Exterior Roller Shade, 8'×8'$239.95✓ confirmed in stockView
    Do it BestShelterLogic Heavyweight Shade Sail, 16'×16'$463.80⚠ phone to confirm stockView
    KooymanSunshade cloth, triangle 3–3.6 m (several colours)$51–$122⚠ webshop closed — phone firstView
    KooymanShadow Comfort sunshade, square 5 m$479.99⚠ webshop closed — phone firstView
    KooymanSunshade mounting set (square, A4/M8) + pole/peg/rope kit$65–$190⚠ webshop closed — phone firstView

    The PriceSmart Coolaroo roller shade is the standout: it is the exact product class for west-facing openings (drops outside the window, breathable knit so wind passes through), it is confirmed in stock, and two of them cover the worst openings for under $500. H&B carries no shade sails — checked.

    Where to get the plants

    NurseryWhereWhy goContact / link
    NCC Garden Centre (government)Codrington House, St. MichaelOrnamental plants and trees at government prices; the NCC grows natives (incl. sea grape) for coastal replanting. Mon–Sat.(246) 536-0617
    Seedburst NurseriesGibbons-Boggs Rd, Christ ChurchOne of the most diverse private nurseries on-island. Mon–Sat.Listing
    Plant Nation Garden CenterSt. Patrick's, Christ ChurchExotic plants and fruit trees; active on Facebook for stock questions.Facebook
    Landmark NurseriesPortvale, St. JamesSeedlings and decorative plants. Mon–Sat.(246) 421-5263
    Nature CareChrist ChurchNursery and garden centre with a live webshop — plants, potting mix and planters in one trip.Webshop
    Stock honesty No Barbados nursery publishes live stock online, so species availability is phone-first. All three recommended species are common on-island; frangipani in particular also grows readily from a free cutting — a 60 cm branch left to dry for a week and planted in sand roots in weeks.

    The trees — what to plant, what to avoid

    Plant these on the west/northwest arc

    Sea grape main shade screen

    Caribbean native; salt, wind and drought proof; big round leaves give real shade. Routinely pruned into a dense 3–5 m screen, which keeps it controllable near the AC units and off the neighbour's side [7]. Not listed as foundation-aggressive; plant 3 m+ off the wall. Expect some large-leaf litter.
    ✓ best screen Species guide

    Frangipani near-wall accents

    Small root ball, explicitly rated safe beside walls, pools and planters [8]; near-zero maintenance; thrives everywhere in Barbados. Drops leaves in the dry season — fine, because the heat problem is the wet season, when it is in full leaf. 5–8 m, easily pruned.
    ✓ safest roots Root FAQ

    Pride of Barbados gap filler

    The national flower; bulletproof locally, fast, 3–4 m shrub height. Not a shade canopy — use it under windows and between the bigger trees.
    ✓ harmless

    Placement rules

    • 3–4.5 m (10–15 ft) off the west wall — standard foundation-safe distance for small/medium trees [9].
    • Cover the arc from due west round to northwest — the summer sun sets north of west here, and the NW corner also shades the deck in late afternoon.
    • Keep 60–90 cm clear around each condenser (living room, bedroom, gym), open above — wherever they sit. Planting, deck furniture and any future roller screen must not form a pocket that traps their hot exhaust. Shade the house, not the unit [6].
    • Nothing on the eastern side. The gap is too narrow; anything there would end up over the neighbour's boundary.

    Avoid these, even though they're everywhere in Barbados

    TreeWhy not
    Ficus / rubber tree / banyanNotorious destroyers of foundations, walls and drains
    Flamboyant (Royal Poinciana)Aggressive surface roots lift slabs; far too big for this lot
    African tulip treeBrittle limbs in storms; invasive
    Mahogany, breadfruitGreat trees, wrong scale this close to a house and neighbour
    Running bambooSpreads under the boundary into the neighbour's lot

    In the ground or in containers?

    Both routes work at Lot 922 — and the smart answer is a mix. Plant the main sea grapes in the ground for the real canopy, and use large containers for frangipani and a movable screen right against the hottest wall, where in-ground roots would be too close.

    Straight in the ground

    Pick this for: the 2–3 sea grapes on the west/NW arc.
    Pros: the only way to get a real 4–5 m shade canopy; almost zero watering once established; cheapest.
    Cons: permanent — position must be right the first time; 3–4.5 m minimum off the wall; 3–5 years to useful shade.
    ✓ main shade canopy

    In large containers

    Pick this for: frangipani accents, Pride of Barbados, and a pruned sea-grape screen row.
    Pros: zero root risk, so pots can sit 0.5–1 m from the wall (where trees never could); movable for storms and experiments; instant placement.
    Cons: smaller plants (2–3 m screen, not a canopy); daily moisture checks in the dry season; root-prune or repot every 2–3 years.
    ✓ near-wall screen + accents

    Option A — planting in the ground, step by step

    1. Buy the biggest healthy specimens you can transport (inspect leaf undersides for pests; reject stretched or root-bound plants). Confirm stock by phone first.
    2. Mark positions before digging: 3–4.5 m off the west wall, spread across the west-to-northwest arc, 60–90 cm clear of every AC unit's airflow, and clear of any buried water or drain lines. Live with the marks for a day.
    3. Dig wide, not deep: a hole 2–3× the width of the root ball but the same depth. Planting too deep is the classic tree killer. Rough up the hole's sides so roots can penetrate.
    4. Backfill with the same soil you dug out — no bags of "improved" soil in the hole, or the roots circle inside the comfortable pocket instead of anchoring. Water as you backfill to settle it. Plant at the exact nursery depth.
    5. Build a watering basin: an 8 cm soil ring at the hole's edge, then 5–8 cm of mulch, kept 10 cm clear of the trunk.
    6. Water deeply 2–3× a week for the first 2–3 months (keep going through the dry season), then taper off. Deep and infrequent beats daily sprinkles — it drives roots down.
    7. Stake only if trade winds rock the root ball — loose ties, and off within 12 months so the trunk strengthens.
    8. Shape the sea grapes into a screen from year one: light pruning several times a year holds them at 3–5 m dense growth and keeps everything off the neighbour's side [7].

    Option B — growing in containers, step by step

    Distilled from your own Container Gardening in Barbados guide (in your Google Drive), applied to these specific trees.

    1. Choose a 50 L+ pot with real drainage holes — these are trees, not herbs. Light-coloured plastic or fibreglass is best in west sun (dark pots cook roots; terracotta dries out fast in wind). Never rely on a gravel layer in an undrained pot.
    2. Position the empty pot first. One litre of water weighs 1 kg — a filled 80 cm pot plus wet mix and plant approaches 100 kg. Set it 0.5–1 m off the wall section you want shaded, on pot feet so the drain holes stay open. No saucers outdoors: standing water breeds mosquitoes (Barbados health guidance is explicit on plant saucers).
    3. Fill with bagged container mix, never yard soil — yard soil compacts in a pot and drowns roots. If the mix is very light, blend roughly 3 parts mix to 1 part mature compost, and stop there.
    4. Plant at nursery depth, leave 3–5 cm of watering space below the rim, and water slowly until it drains from the bottom.
    5. Acclimatise for 1–2 weeks: bright shade first, then morning sun, then the full west exposure. Nursery-shade plants scorch if moved straight into afternoon sun.
    6. Water by evidence, not calendar: finger 3–5 cm into the mix each morning — cool and moist means wait, dry means water until it drains. In the dry season expect to water most days; frangipani forgives a miss, sea grape in a pot does not.
    7. Feed with a slow-release fertiliser at the label rate (Osmocote-type, below). If the bagged mix already contains fertiliser, wait out the period printed on the bag. More is not better in a pot.
    8. Watch the outgrown-pot signs: water rushing straight through, wilting the day after a thorough soak, roots circling or escaping the holes. Every 2–3 years, root-prune and refresh the mix, or step up one pot size.
    9. Have a storm plan now, not in November: decide where each pot goes when an alert is issued, and move them before the wind arrives — a heavy pot is not an anchor, it is future debris. This mobility is exactly why containers win near the house.
    Household cautions from your guide Pride of Barbados seeds carry a toxicity caution — place it away from where children or pets chew things. And skip the tempting "screen" plants Biodiversity Barbados flags as invasive: snake plant, MacArthur palm, flamboyant.

    Container-route shopping list

    ItemStorePrice BBDStatusLink
    E&K Flowerpot 80 cm (tree-sized)Kooyman$199.99⚠ webshop closed — phone firstView
    Classic poly-terracotta pot, 20 inCarter's$99.80✓ listed in stockView
    Atenas glazed planter, XLGajah Home$116.40✓ listed in stockView
    Ariana planter, 20 inMarshall's Trading$80.70✓ listed in stockView
    Pindstrup potting mix, 80 LH&B Hardware$55.99✓ listed in stockView
    Soilmate growing mix, 30 LNature Care$24.00✓ listed in stockView
    Black Gold potting mix, 2 cu ftMarshall's Trading$55.31✓ listed in stockView
    Osmocote Smart-Release Plant Food Plus, 2 lbCarter's$43.26✓ listed in stockView

    Budget for the container route: roughly BBD $150–$260 per planted pot (pot + mix + fertiliser + plant), so a three-pot near-wall screen lands around $500–$750 — and it starts shading the wall the day you set it down.

    Your next steps

    1. PriceSmart run: pick up 1–2 Coolaroo 8'×8' exterior roller shades ($239.95 each) and mount them outside the worst west-facing windows. This is the only same-week fix, so it goes first.
    2. Phone Carter's, H&B and Kooyman: price a 12–14 in turbine vent (~$350, all three list stock) and ask who carries double-sided foil insulation / radiant barrier rolls. If nobody stocks the foil, freight-forward a Reflectix roll rather than gambling on a Do it Best special order.
    3. Book a roofer for half a day: fit 1–2 turbines high on the roof with open soffit intake, and staple the foil barrier under the rafters (foil face down, air gap). You should feel the ceiling rooms improve on the first hot afternoon.
    4. Decide ground vs containers per zone (see the section above): in-ground sea grapes for the canopy, containers for the near-wall screen and accents. Containers can start this weekend; in-ground should go in before the wet season ends.
    5. Call the NCC Garden Centre (246) 536-0617: ask for sea grape and Pride of Barbados; ask Nature Care, Seedburst or Plant Nation for frangipani if the NCC is short. Nature Care's webshop also covers the pots and mix in the same trip.
    6. Keep the deck's retractable roller screens in the renovation plan — right idea for the north side's late-afternoon exposure — but design them to leave any condenser they pass 60–90 cm of open airflow.
    7. When the re-roof eventually happens, that's the moment for light "cool" shingles or white metal — never a coating over the existing shingles [10].
    8. Re-assess next summer. Only then decide whether one AC unit still needs upgrading, and size it to the new, lower load.

    Sources

    Studies and references [1]–[9]
    Built for Atiba — Lot 922 heat mitigationGenerated 2026-08-15