A third of MPs are unhappy with the cleanliness of toilets inside the House of Commons, a study has revealed.
One in five also said they were dissatisfied with Parliament's dining rooms, restaurants and cafes, according to the House of Commons Survey of Services 2012.
A total of 177 MPs and 961 of their staff completed the annual questionnaire asking for their feedback on the quality of services and facilities in the Palace of Westminster.
More than 80% of those surveyed said they were more than satisfied with the levels of general cleaning across the parliamentary estate.
But many complained their offices were only cleaned superficially and that the lavatories in the Commons were too dirty.
The study, conducted by private market research company SPA Future Thinking at a cost of between £21,710 and £27,790, said:
"Although satisfaction with general cleanliness was fairly high, substantial proportions were dissatisfied with the cleaning of their office (17% of members and 25% of members' staff were dissatisfied) and with the cleanliness of toilets across the Estate (a third of members and their staff were dissatisfied)."
Toilets in the Norman Shaw North building are in particular need of regular deep cleaning and modernisation, politicians said.
Around 20% of MPs were unhappy with the dining rooms, restaurants and cafeterias in Parliament and expressed dissatisfaction with the Commons Tea Room and Smoking Room (where, contrary to popular myth, smoking is banned).
Both members and staff expressed concerns about the price, quality and range of food on offer and complained of a perceived lack of value for money.
Some said meals are too elaborate and called for more traditional options on the menu.
The quality of food in the Houses of Parliament is documented on a daily basis by a popular twitter account, CommonsFoodHell.
In terms of security, the proportion of MPs who said the felt "very secure" of "extremely secure" stood at 57% - dropping from 68% in 2010.
A number also said Parliament could be more environmentally-friendly and suggested more recycling points, motion sensor lighting and a more efficient heating system.
The House of Commons Service employees around 1,700 people who support MPs in performing their parliamentary duties.
The majority of politicians and their workers - 92% and 94% respectively - were at least satisfied with the service overall, January's 13-page survey found.
Just over a fifth (22%) of MPs said their overall satisfaction had decreased since 2010.