Designate a free climate-shelter network in existing public buildings

Mechanism

Rather than building dedicated cooling facilities, the city designates buildings it already owns or partners with (libraries, schools, museums, civic centers, sports facilities, pharmacies as micro-shelters) as an official climate-shelter network under published standards:

• indoor temperature kept at or below 26 C
• free entry with no purchase or ID requirement
• accessibility, seating, and drinking water
• mapped and signposted so residents know where the nearest shelter is

Coverage grows by adding sites, which costs far less than new construction; school conversions can pair shelter designation with depaving and greening of yards.

Where it fits

City scale. Suited to cities with a dense stock of public buildings and a hot season that strains homes without air conditioning. It provides the refuge layer of a heat plan—somewhere to go during the hottest hours—complementing outreach layers that find and move vulnerable people.

Evidence

Barcelona is the reference deployment: its network grew from 70 sites in 2020 to 368 in 2024 and over 500 by 2026, plus pharmacy micro-shelters, with 98 percent of residents within a 10-minute walk. An EU-funded project (GBG_AS2C, 3.99 million euros ERDF) converted 11 schools. Maricopa County, Arizona illustrates failure and repair modes: daytime-only centers failed people experiencing homelessness, and a shift to 24/7 respite centers coincided with heat deaths falling from 645 (2023) to 430 (2025).

Implementation path

1. Audit public buildings for temperature, water, accessibility, and capacity; designate an initial network.
2. Publish standards (temperature ceiling, free access, water) and a public map.
3. Extend opening hours to match heat peaks: evenings, weekends, holiday months, and overnight respite where street homelessness is significant.
4. Add partner sites (pharmacies, community organizations) as micro-shelters.
5. Run awareness campaigns and measure awareness and actual usage by vulnerable groups, not just site counts.

Trade-offs

• Coverage on a map is not protection: documented gaps include low public awareness (only about one third of Barcelona residents knew the network existed in a 2023 survey), sites closed on weekends and in August exactly when heat peaks, and social barriers for migrants and marginalized groups.
• Buildings keep their primary functions; libraries and museums may resist non-typical users unless staff are trained and mandated to welcome them.
• Keeping many buildings at or below 26 C has energy costs, and school sites are typically unavailable in the hottest month without specific arrangements.
• Without transport support, the network serves the mobile; the least mobile residents still need door-to-door layers.