# Painting outside in a GTA fall: what the data sheets actually allow (2026)

**URL:** <https://home.renovation.reviews/t/painting-outside-in-a-gta-fall-what-the-data-sheets-actually-allow-2026/48626>\
**Category:** Painting & Wall Treatments\
**Tags:** toronto, gta, exterior-renovation, painting, primer, fall\
**Created:** [October 31, 2026, 1:47pm UTC](https://home.renovation.reviews/t/painting-outside-in-a-gta-fall-what-the-data-sheets-actually-allow-2026/48626 "2026-10-31T13:47:59Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![Gary\_From\_LFBuilders](https://home.renovation.reviews/user_avatar/home.renovation.reviews/gary_from_lfbuilders/32/17159_2.png) [@Gary\_From\_LFBuilders](https://home.renovation.reviews/u/Gary_From_LFBuilders)\
**Post date:** [October 31, 2026, 1:47pm UTC](https://home.renovation.reviews/t/painting-outside-in-a-gta-fall-what-the-data-sheets-actually-allow-2026/48626/1 "2026-10-31T13:47:59Z")

</div>

_From LF Builders, the renovation company behind this forum. Data sheet figures checked October 31, 2026; manufacturers revise them, so check the sheet for your exact product code._

**Short answer:** It depends on the can, not the calendar. Several premium exterior acrylics now list a minimum of **35°F (1.7°C)**. Sherwin-Williams Duration and Benjamin Moore Aura’s current Canadian data sheets both do. Older sheets, and many other products, set 40°F or 50°F. The minimum applies to the air, the surface _and_ the paint, and the paint has to stay above it while it dries, so the overnight forecast matters more than the afternoon high.

## What two common exterior paints say

| Product | Minimum | Conditions on the sheet |
| --- | --- | --- |
| Sherwin-Williams Duration Exterior Acrylic | 35°F (1.7°C) | Air, surface and material all above 35°F and at least 5° above the dew point. Don’t apply if temperatures may drop below 35°F within 48 hours. Large metal siding and unfilled block need 50°F. |
| Benjamin Moore Aura Exterior (Canadian sheets, e.g. F629, F634) | 1.7°C (35°F) surface | Don’t apply below the minimum air or surface temperature. Cool, humid weather lengthens dry, recoat and service times. Some older US sheets list 40°F. |

## Primer is its own product

Your topcoat’s minimum isn’t necessarily your primer’s. Read the primer’s data sheet too and work to whichever of the two is stricter; a primer that never cured properly takes the topcoat with it.

## Fall checklist for a late exterior job

- Check the **48-hour** forecast, not today’s high. Frost or freezing overnight is what ruins a coat that looked fine at 3 p.m.
- Measure the **surface** , especially north faces and anything in shade. Siding can be colder than the air.
- Stay **5° above the dew point** , or follow what your product’s sheet says. Moisture settling on paint that hasn’t set yet is a common reason late-season coats look blotchy or cure poorly.
- Start after the morning dew burns off and stop early enough for the paint to set before evening.
- Expect **longer recoat times** in cool, damp weather, and plan the second coat around that.

## Painters, weigh in

- What’s the latest date you’ll start an exterior job in the GTA, and what product do you reach for in late October?
- Have you seen a late-season job fail? What went wrong: dew, frost, primer, or the wrong product?

## Sources

- Sherwin-Williams, [Duration Exterior Acrylic Gloss product data sheet](https://www.sherwin-williams.com/document/PDS/en/035777132715/) (3/2026), [Exterior product application FAQs](https://www.sherwin-williams.com/architects-specifiers-designers/products/resources/faqs/exterior-product-application-faqs), [Late-season exterior painting](https://www.sherwin-williams.com/painting-contractors/business-builders/paint-technology-and-application/sw-art-late-season-painting)
- Benjamin Moore, [Aura Exterior Paint](https://www.benjaminmoore.com/en-us/interior-exterior-paints-stains/aura-exterior-paint), [Aura Waterborne Exterior Flat F629 data sheet](https://media.benjaminmoore.com/WebServices/prod/assets/production/datasheets/TDS_0629/F629_TDS_CE.pdf), [Aura Waterborne Exterior Low Lustre F634 data sheet](https://media.benjaminmoore.com/WebServices/prod/assets/stage/datasheets/TDS_0634/F634_TDS_CE.pdf)