Multifamily · 3-minute read

How to retrofit an apartment building with smart access (without locking residents out).

A practical playbook from 60-unit garden communities to 250-unit mid-rises. The 5-phase approach, how to keep residents in their units throughout, and the most common mistakes to avoid.

By Ryan Huneidi, Co-Founder & Owner · Updated October 2026

Why this is tricky

Retrofits are harder than new construction.

New construction is easy: you spec the doors before they're installed. Retrofits are hard because every door is already there, every resident already lives behind one, and you can't pause operations while you swap hardware. The good news: retrofits are routine when they're phased properly. Here's the playbook.

In our experience, the biggest predictor of a smooth retrofit isn't the platform or the budget. It's how the project is phased.

The 5-phase playbook

How we phase a retrofit so residents keep access.

Walk-through & auditEvery door, every common area, every IT closet. We document existing locks, existing wiring, the network, and resident-facing operations. 1–2 days on site.

Network preparationBefore any access hardware goes in, the network gets prepped. VLAN segmentation, switch upgrades, additional drops where needed. Done quietly over 2–3 weeks.

Common areas firstPool, gym, mailroom, parking gates get smart access before unit doors. Residents see the new system in low-stakes spaces and start to trust it.

Unit doors, phased by building or stackBuilding by building, stack by stack, floor by floor. Residents are notified 7+ days in advance. Each unit takes 20–45 minutes. We do swap days, not swap weeks.

Resident rollout & first-week supportResidents get setup instructions, app invitations, and cards or fobs before their door changes over. We stay on site for the first days after each phase to answer questions and fix credential issues. Then the property team gets training and the as-built documentation.

Common pitfalls

What goes wrong when retrofits are done poorly.

Mistake 1: Doing the network last. If the network can't support the new readers, you discover this at cutover. We always do network first.

Mistake 2: All-at-once cutover. Some integrators try to switch the entire building over one weekend. Residents get locked out of their own homes. Reputational damage is real.

Mistake 3: Mobile-only credentials. A meaningful percentage of residents need physical credentials — residents without a reliable smartphone, family members without phones, people who lose phones. Mobile-only forces a wave of complaints. Every access platform we install supports both.

Mistake 4: Skipping resident communication. Residents need 7–14 days notice, a clear explanation of what's changing, and easy onboarding. We send pre-install emails, hold lobby Q&A, and have someone on site for the first 3 days after each phase.

Mistake 5: Treating PMS integration as a phase-2 thing. If your access platform doesn't sync with Yardi/RealPage/AppFolio from day one, your property manager spends every move-in day manually adding access. Configure this in phase 1. PMS sync is one of the main differences covered in Salto KS vs Allegion Zentra.

Planning a retrofit?

We plan retrofits around your residents.

Free walk-through, then a line-item design with three options. We'll look at your existing infrastructure and show you how we'd phase around it.

Book a free walk-through