How can I soundproof this window?

[infoscion]

Hi everyone, 

I just moved into an apartment near a busy road. The window in the bedroom lets in a lot of noise at night.

bedroom window

Not sure where to start, it's a rental as well so I can't make any permanent changes. 

I don't mind a solution that fully blocks off access to the window until I move out.

Kind regards,

Daniel

[infoscion]

Would slotting something like this in there work? 
https://www.bunnings.co.nz/expol-2400-x-1200-x-50mm-h-grade-polystyrene-thermaslab_p0855613

Are there more suitable materials? Or simply a better way to go about this? (I'm fairly new to any sort of DIY 😅)

[JacobZ]

Hi @infoscion,

Thank you for your question and welcome to the Bunnings Workshop community, it is fantastic to have you join us.

Unfortunately, It would be impossible to truly soundproof this window without making alterations outside the boundaries of a rental agreement, however, there are ways to reduce the sound transfer that will be helpful for you. 

The Expol 2400 x 1200 x 50mm H Grade Polystyrene ThermaSlab would certainly be a great place to start in reducing the sound transfer through this window.

You might like to start by grabbing a single sheet and cutting it so it can be held in place by the friction on the side walls. You can cut these sheets to size using a Craftright 18mm Snap Off Knife.

As the solution needs to be removable, and won't be permanent, you could start with this and add additional layers if a single layer doesn't dampen the sound enough.

You might also like to check out Options for soundproofing windows, How to sound proof a bedroom? and Double glazed windows to reduce road noise for some other information that might help.

Let me know what you think and if you have any further questions.

Jacob