Inside, men are cutting panes for one of Bosnia's growth industries. Since the signing of the Dayton peace plan at the end of November, Interglass has fitted around 200 to 300 square metres of glass each working day.
Gone is the plastic sheeting, marked in blue with the acronym of the UN High Commissioner for Refugees. Ubiquitous in the war, it has been replaced with glass. Interglass, the largest private glass company in the city, has tripled its pre-war workforce to accommodate the boom.
But the reconstruction of Bosnia is dormant: the only rebuilding to date has been done by Nato troops, aid agencies, local entrepreneurs and householders. None of the money pledged by foreign governments has reached Bosnia, according to international civilian officials.
Those working for Carl Bildt, the High Representative in charge of co- ordinating reconstruction, say the immediate problem is not a lack of cash but a surfeit of bureaucracy, which threatens to exacerbate the obvious dangers of demobilising thousands of soldiers who have no jobs and no prospects.
The World Bank, which will administer the aid donated at this weekend's conference, has rigorous and time-consuming procedure for dispersing funds, aimed at ensuring the money is accounted for and spent on worthwhile projects. The problem, say Mr Bildt's staff, is that Bosnia needs cash now, so that the unemployed can be put to work paving the ground for larger projects.
"There is a huge conflict between the political requirements on the ground and the normal working processes of the World Bank," said Duncan Bullivant, a spokesman for Mr Bildt. He maintains that the priority is first to repair infrastructure and then to provide work for the thousands on both sides who must be demobilised by the 18 April under the Dayton plan.
"They need jobs now to get them off the streets," Mr Bullivant said. Mr Bildt envisages "Depression-style" hiring, in which locals would be employed for casual work such as clearing rubble before the bigger projects begin. If money for such action is not forthcoming "it's going to create a sea of opportunity for political extremism", he said.
There are no big foreign reconstruction projects under way. Western troops are working to repair electricity lines in eastern Bosnia for example just as British troops have rebuilt a bakery in Gornji Vakuf.
In Tuzla, 16 British fire fighters are helping to renovate a kindergarten, with money provided by War on Want and Norwegian Peoples Aid.
The success of the Dayton peace plan will depend on translating political accords into material benefits for the exhausted people of Bosnia and that will require a large - and swift - injection of cash. Only the hope of prosperity will silence the siren songs of nationalism.