What has happened to my new lawn?!

Hi,

I bought a new build last summer and now winter has hit my grass looks like this :(

note the badly affected area isn’t getting sunlight and much wind as it is blocked by the garage during the winter. What do I do going forward and will this grow back in spring or need re seeded? Thanks I’m advance

 

Yes give the whole lawn a over seed but before you do that spike the lawn with a garden fork at least 6inch down , builders trample the lawn area and heavy compact it with machinery etc . Forking the lawn will help relieve the compaction and help drain excess water and allow air / water and nutrients down to the root system. The turf probably only been laid on a couple of inch of top soil and they don't tend to lightly compact the top layer to remove air causing bumps / divots and dying grass when it eventually settles , they do bit of a rough job .

 

I would also give it a feed and top dressing at the same time.
Rusty