def ASHRAE_k(ID):
    r'''Returns thermal conductivity of a building or insulating material
    from a table in [1]_. Thermal conductivity is independent of temperature
    here. Many entries in the table are listed for varying densities, but the
    appropriate ID from the table must be selected to account for that.

    Parameters
    ----------
    ID : str
        ID corresponding to a material in the dictionary `ASHRAE`

    Returns
    -------
    k : float
        Thermal conductivity of the material, [W/m/K]

    Examples
    --------
    >>> ASHRAE_k(ID='Mineral fiber')
    0.036

    References
    ----------
    .. [1] ASHRAE Handbook: Fundamentals. American Society of Heating,
       Refrigerating and Air-Conditioning Engineers, Incorporated, 2013.
    '''
    values = ASHRAE[ID]
    if values[2]:
        return values[2]
    else:
        R = values[3]
        t = values[4]/1000. # mm to m
        return R_to_k(R, t)
r'''Returns thermal conductivity of a building or insulating material
    from a table in [1]_. Thermal conductivity is independent of temperature
    here. Many entries in the table are listed for varying densities, but the
    appropriate ID from the table must be selected to account for that.

    Parameters
    ----------
    ID : str
        ID corresponding to a material in the dictionary `ASHRAE`

    Returns
    -------
    k : float
        Thermal conductivity of the material, [W/m/K]

    Examples
    --------
    >>> ASHRAE_k(ID='Mineral fiber')
    0.036

    References
    ----------
    .. [1] ASHRAE Handbook: Fundamentals. American Society of Heating,
       Refrigerating and Air-Conditioning Engineers, Incorporated, 2013.