Homeowners ask how long the panels take to put on the roof. That is the wrong question, and it is why so many solar projects feel like they stalled. A grid tied solar installation is mostly paperwork and permissions with a day or two of roof work in the middle. The array can be fully installed, wired and weathertight and still be legally switched off, waiting on a piece of correspondence.
Knowing the sequence before you sign changes the conversation with every contractor you talk to, because you will be asking about the steps that actually control the date.
What a grid tied solar installation has to clear before it switches on
There are four approvals, they run partly in parallel, and each one can send you back a step.
The interconnection application. This goes to your electric utility and it asks permission to put power onto their distribution system. The utility reviews the equipment, the system size and the circuit it will feed. On a straightforward residential system this is a review rather than a study, but the review is a queue and the queue has a length.
The building and electrical permit. This goes to the local authority having jurisdiction, which for central Ohio homeowners is the city or the county depending on where the house sits. It covers the electrical work and, on most roof mounts, a structural check of the array’s load on the framing.
The inspection. A physical inspection after installation and before the system is allowed to run. Fail it and you are rescheduling, not fixing on the spot.
Permission to operate. The final letter or notice from the utility saying you may energise. Almost nobody expects this step and it is routinely the one that adds weeks. Until it arrives, an otherwise finished array stays off.
A meter exchange often sits inside that last step, because the billing arrangement for exported power needs a meter that measures in both directions.
The roof decides more than the panels do
Before any of the above, the roof gets a hard look, and this is where honest contractors lose sales to optimistic ones.
Array life is measured in decades. If the roof has under ten years left, the panels come off and go back on when it is replaced, and that is a cost nobody wants to meet twice. Replacing the roof first is almost always the cheaper sequence.
Framing matters too. Older Ohio homes with true dimensional lumber usually take an array without difficulty. Some later trussed roofs need the loads checked before anything is fastened.
Then orientation and shading. South facing planes produce most, east and west less, and north facing planes rarely justify panels at all. Shading is the harsher constraint, because a single tree that clips the array for two hours in the afternoon can cost more production than the orientation does. Ask for a shade analysis of the actual roof rather than a generic estimate for the region.
The electrical side that quotes skip
The array connects to the house through the main service panel, and that connection is bounded by the Code. A backfed solar breaker feeds current onto the bus from the opposite end to the main, and the Code limits the main breaker and the backfed breaker together against what the bus is rated to carry. A panel that seems to have room may not accept the solar breaker at all.
Three answers exist: derate the main breaker, connect on the supply side ahead of the main, or replace the panel. Which one applies depends on your panel, and it is worth settling before the contract rather than as a change order. Our electrical panel work is often the first step of a solar project rather than an extra.
Rapid shutdown is the other requirement worth knowing by name. The Code requires that the conductors on the roof can be de-energised quickly for firefighters, which is handled either with microinverters or with module level electronics on a string system. It affects equipment choice, and it is not optional.
If a battery or a standby generator is anywhere in your plans, say so now. Backup power changes the wiring topology because the loads you want backed up have to be separated onto their own panel, and retrofitting that later means opening work you have already paid for. The trade-offs between the two are covered in our comparison of battery backup and a standby generator.
Sizing, and why bigger is not automatically better
The billing arrangement for exported power in Ohio is set by your utility under state rules, and the terms of that arrangement decide whether a system that produces more than you use is worth building. This is the single most important question to put to a solar contractor, and the answer should be specific to your utility rather than a general statement about solar.
Design starts from your actual consumption. Twelve months of usage history, not an average, because winter and summer look nothing alike in central Ohio. From there the design accounts for roof area, orientation, shading and the equipment. A proposal that starts from a system size rather than from your usage has the logic backwards.
Ohio weather is not the obstacle people assume. Panels produce in cold conditions, and in fact run more efficiently at lower temperatures. Snow cover matters, and so does the flatter winter sun angle, which is exactly why the design is based on a full year rather than a good month.
What a good solar proposal contains
It should name the modules and the inverters by manufacturer and model, not by wattage class alone. It should show the array layout on your roof, with the shading accounted for. It should state the production estimate for a full year and name the assumptions behind it. It should say what happens at the main panel, in words, including whether a derate, a supply side connection or a panel replacement is required. It should list the permits and the interconnection application as separate line items with who files each. It should state the warranty terms for the modules, the inverters, the racking and the workmanship separately, because they are different lengths. And it should be honest that permission to operate is outside the contractor’s control.
If you want that kind of assessment on a central Ohio home, start at the contact page. The solar installation and electrical departments do the roof and the panel walkthrough together, and the load side of the same question is covered in our guide to panel capacity for electrification.
Frequently asked questions
How long does a grid tied solar installation take from signing to switch on?
The physical installation is usually one to three days for a residential roof mount. Everything else is approvals: the interconnection application with your utility, the building and electrical permit, the inspection, and finally permission to operate. Those run in weeks rather than days and they are not fully under a contractor’s control. Ask any bidder for their recent experience with your specific utility and your specific jurisdiction rather than for a generic timeline.
Do solar panels work in Ohio winters?
Yes, and the cold itself is not the problem. Photovoltaic modules are more efficient at lower temperatures, so a clear cold day is good production weather. What reduces winter output is the shorter day, the lower sun angle and snow sitting on the array. That is why an honest design is built from a full year of production modelling and a full year of your own usage, not from a summer month.
Will my roof need replacing before solar goes on?
If it has less than about ten years of life left, replace it first. An array lasts decades, and taking panels down and putting them back to reroof underneath is work you pay for twice. A contractor who does not raise the roof’s age and condition before quoting is not looking hard enough.
Does adding solar mean I can run my house during an outage?
Not on its own. A standard grid tied system shuts down when the grid goes down, which is a safety requirement so that it cannot energise lines that utility crews are working on. Running through an outage needs battery storage with the right inverter, or a generator, and the loads you want backed up have to be wired onto a separate panel. Decide this before installation, because retrofitting it means reopening finished work.
Why can my system be finished but not turned on?
Because permission to operate is a separate step from installation and inspection. The utility issues it after its own review is complete, and a meter exchange is often part of it. An array can be fully installed, inspected and weathertight while that notice is still outstanding. It is normal, it surprises almost everyone, and it belongs in the schedule conversation at the start rather than at the end.