Can I tee off from the cold feed to a combi boiler?

[Havago]

I am installing a washing machine. The flat has a combi boiler. The rising main enters under the sink, goes to a stopcock, then goes up to the kitchen sink and splits off to the combi boiler. I want to tee off from this cold feed to the boiler to feed the washing machine. Is this OK? I'm worried it might reduce the pressure to the boiler, but I can't see any other way of doing it. It's more convenient for me to tee off from just underneath the boiler rather than from the pipe to the kitchen sink, but as far as I understand it, teeing off from either of these two pipes would reduce the pressure the same amount anyway.
Would really appreciate a swift answer as I need to do this job tomorrow.
Thank you very much!

 

[alex444]

You are right, it doesn't matter where on the cold it is really.
I doubt it'd reduce the pressure much or for long anyways, its only gonna fill the washer every now and then.
If teeing in the feed to the boiler makes the job easier then go for it.

Alex

 

[Havago]

Thanks so much! Happy days.