Situated right behind the president's house (Temple Trees) in Kollupitiya, Colombo, the YWCA national headquarters is a dorm that is perfect for women travelling alone, women who need to stay for long durations, and for couples. I stayed here for 10 days, was charged SL Rupees 880 a night, and was given a room that was well lit, and very clean. Bed linen was changed every two days. I splashed some tea on mine once, and when I told them, the warden had the linen changed without fuss.
The YWCA is essentially a working women's hostel, so there are many Sri Lankan girls who stay here on a yearly basis. It is their home. So there are regular bells for hot water at the boiler, bells for breakfast (7am to 8am) and dinner (8.30pm-9.30pm). Guests can buy a full breakfast (toast, butter, jam, fruit, tea pot) for SLR 300, or buy puttu+tea, idiyappam+tea, or other local food for around Rs. 150 each. I did the latter. Lunch of rice and curry is Rs. 150 per packet, and is excellent (beef/fish/chicken curry, 3 types of veggies, lentils, crisps, rice).
About the rooms-- they are basic, but clean and breezy (it also has a fan). There are two single beds, bed stands, a dresser and two clothes hangers.
Rooms are usually on share basis, at least with one other person. I luckily had a roommate only 2 nights of my stay, but that was good company too. (If you don't like your roommate for good reason (cleanliness, noise, etc), politely inform the warden. She tries to help. Common bathrooms are at the end of the hall and are clean.
There are no time curfews.
The other YWCA facility, YWCA the international guesthouse in Union Place, is very pretty and has non-share single/double rooms but is SL Rupees 4400. Both the facilities are located centrally in Colombo, close to Galle Face, Pettah, Fort station and bus stand, shopping areas etc.
I would stay there again for sure. It is the best value option in Colombo.