What Actually Happens on Install Day: A Homeowner's Guide to Getting Double Glazing

Kali Pentecost
3 minutes ago
6 min read

You've had the consultation, approved the quote, and picked your glazing solution. But there's often one question homeowners don't ask out loud until the week before install: what is this actually going to be like?

Will the house be a mess? Do you need to take the day off work? Can the kids still get to school on time? Will you be living with sheets of plastic over your windows for a week? It's a fair set of worries, letting a team into your home to work on every window and door is a bigger disruption, in theory, than most home improvement jobs. In practice, for most Bay of Plenty homes, it's far more contained than people expect. Here's what to actually plan for.

Before the Truck Arrives

By the time install day comes around, most of the groundwork has already happened. Your windows and doors will have been carefully measured on-site during the second consultation, and particularly for retrofit work, the new glazing units are manufactured off-site to those exact measurements ahead of time. That matters for install day, because it means the team isn't cutting, shaping, or fabricating in your living room. They're fitting pre-made units into place.

The main thing worth doing in the days before: clear a bit of space around each window and door that's being worked on. Move furniture, ornaments, or curtains away from the immediate area, and if you've got blinds or curtains that are tricky to remove, it's worth asking your installer whether they need to come down or can just be pushed aside.

What Aluminium Retrofit Day Actually Looks Like

If you're retrofitting existing aluminium joinery, rather than replacing the frames entirely, install day is generally the more straightforward of the two. Because the process works with your existing frames rather than removing them, there's no demolition, no re-plastering, and typically no need to redecorate afterwards.

For most homes, a full retrofit is completed within a day or two, though larger homes or ones with harder-to-access windows can take a little longer. Your consultant should be able to give you a realistic timeframe for your specific property during the quote stage, since it depends on the number of windows, the type of joinery, and how accessible each one is (single storey is generally quicker than multi-storey).

Throughout the day, expect:

Windows being worked on in small batches, rather than the whole house being opened up at once
Some noise, particularly during the removal of old glazing
Small amounts of glass debris and dust around each work area, which a careful installer will clean up as they go
The team ensuring no window is left open or insecure overnight if a job runs across more than one day

You don't generally need to vacate the house for a retrofit. Most homeowners carry on with normal daily life around the team, though it's worth planning around nap times or quiet work calls if the team is working near a nursery or home office that day.

What Timber Retrofit Day Actually Looks Like

Timber retrofit works a little differently to aluminium, and the process depends on which of two approaches suits your joinery.

The traditional method involves your existing timber window sashes being removed from the home entirely. Temporary glass is fitted in their place straight away, so your home stays safe and weathertight while the work is underway. Your original sashes are then taken back to the factory, where they're carefully planed down to make room for the new double glazed units before being reinstalled into the timber frame. Once that's done, the team returns to fit them back into your home. Because of the factory turnaround involved, this process typically takes a minimum of a week from removal to reinstallation, so it's worth planning around a longer timeframe than a straightforward aluminium retrofit.

The replacement sash method is a faster alternative, and it runs more like a standard aluminium retrofit. Rather than taking your existing sashes away to be reworked, new double glazed timber sashes are manufactured off-site ahead of time, based on measurements taken at your second consultation. On install day, the team simply removes the old sashes and fits the new ones in their place, all done on-site, typically within a day or two.

Which method is right for your home usually comes down to the condition and character of your existing joinery, and it's something your consultant will talk through with you at the quote stage. Either way, expect the same general on-the-day considerations as an aluminium retrofit, some noise, minor dust and debris around each work area, and a team that keeps your home secure throughout.

What Full Replacement Day Looks Like

If your existing frames aren't suitable for retrofit and you're having a full replacement instead, the process is a bit more involved, since it includes removing the old frames as well as the glass. This can mean:

A longer overall timeframe, particularly if multiple windows or doors are being replaced. Generally a week should be allowed for a standard sized home.
Openings being temporarily weatherproofed between removing the old frame and fitting the new one, so the home stays secure and dry
A bit more dust and general mess around each opening, especially where sealant, flashing, or trim work is involved
Possible repairs or minor touch-ups to interior linings or exterior cladding around the new frame, depending on the age and construction of your home

Full replacement is still a manageable process for most households to live through, but if you have very young children, pets that are easily unsettled by noise and strangers in the house, or you work from home in a way that needs total quiet, it's worth flagging that with your installer ahead of time so the schedule can be planned around it.

Living in the House During the Work

For both retrofit and full replacement jobs, a few practical things make the week smoother:

Pets — dogs in particular tend to be unsettled by unfamiliar tradespeople and open doors. It's worth having a plan for keeping pets in a closed-off area or with a family member for the day.
Access — the team will need clear access to both the inside and outside of each window or door being worked on, so check gate access, side pathways, and any locked areas in advance.
Power and water — installers generally don't need much, but it's worth checking if outdoor power access is required.
Kids and daily routine — most families find they can carry on with school runs, work-from-home days, and normal routines with a bit of flexibility around which rooms are in use when.

After Install: What to Expect

Once your windows and doors are in, there's usually a final check-over to make sure everything opens, closes, and locks properly, along with a clean-up of the immediate work areas. Any offcuts, packaging, or old glazing will be removed from the property, unless instructed otherwise, as part of the job, it's worth confirming this at the quote stage if it's not already clear.

You shouldn't need to do anything further on your end beyond enjoying a quieter, warmer, drier home. If anything feels off in the days following, a window that's sticking, a draught that wasn't there before, we want to know and will come back to sort it.

The Bottom Line

Most of the anxiety around double glazing installation comes from not knowing what to expect and in reality, for the majority of Bay of Plenty homes, it's a contained, professional process that doesn't require moving out, taking extended time off work, or living with major disruption for weeks on end. The best way to know exactly what your install day will look like is to ask directly during your quote: how many days, how many people on site, what access is needed, and what the clean-up process looks like. A good consultant will walk you through all of it before a single window is touched.